diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
new file mode 100644
index 0000000000..1118d9caa2
--- /dev/null
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -0,0 +1,10 @@
+| Q             | A
+| ------------- | ---
+| Bug fix?      | [yes|no]
+| New feature?  | [yes|no]
+| BC breaks?    | [yes|no]
+| Deprecations? | [yes|no]
+| Tests pass?   | [yes|no]
+| Fixed tickets | [comma-separated list of tickets fixed by the PR, if any]
+| License       | MIT
+| Doc PR        | [reference to the documentation PR, if any]
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 123d5aa755..a33841f674 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -12,19 +12,6 @@ If you'd like to contribute, please read the following documents:
 * [Pull Request Template][3]: Template header to use in your pull request
   description;
 
-```markdown
-| Q             | A
-| ------------- | ---
-| Bug fix?      | yes/no
-| New feature?  | yes/no
-| BC breaks?    | no
-| Deprecations? | no
-| Tests pass?   | yes
-| Fixed tickets | #1234
-| License       | MIT
-| Doc PR        | symfony/symfony-docs#1234
-```
-
 * [Backwards Compatibility][4]: Backward compatibility rules.
 
 [1]: https://symfony.com/doc/current/contributing/code/index.html
diff --git a/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php b/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
index 0d8edb29d4..3acac1c9ad 100644
--- a/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
+++ b/src/Symfony/Component/DependencyInjection/Dumper/YamlDumper.php
@@ -89,7 +89,7 @@ class YamlDumper extends Dumper
         }
 
         if ($definition->getFile()) {
-            $code .= sprintf("        file: %s\n", $definition->getFile());
+            $code .= sprintf("        file: %s\n", $this->dumper->dump($definition->getFile()));
         }
 
         if ($definition->isSynthetic()) {
@@ -109,11 +109,11 @@ class YamlDumper extends Dumper
         }
 
         if ($definition->getFactoryMethod(false)) {
-            $code .= sprintf("        factory_method: %s\n", $definition->getFactoryMethod(false));
+            $code .= sprintf("        factory_method: %s\n", $this->dumper->dump($definition->getFactoryMethod(false)));
         }
 
         if ($definition->getFactoryService(false)) {
-            $code .= sprintf("        factory_service: %s\n", $definition->getFactoryService(false));
+            $code .= sprintf("        factory_service: %s\n", $this->dumper->dump($definition->getFactoryService(false)));
         }
 
         if ($definition->getArguments()) {
@@ -129,7 +129,7 @@ class YamlDumper extends Dumper
         }
 
         if (ContainerInterface::SCOPE_CONTAINER !== $scope = $definition->getScope()) {
-            $code .= sprintf("        scope: %s\n", $scope);
+            $code .= sprintf("        scope: %s\n", $this->dumper->dump($scope));
         }
 
         if (null !== $decorated = $definition->getDecoratedService()) {
diff --git a/src/Symfony/Component/HttpFoundation/RedirectResponse.php b/src/Symfony/Component/HttpFoundation/RedirectResponse.php
index a21eb5cc51..e7f47aa259 100644
--- a/src/Symfony/Component/HttpFoundation/RedirectResponse.php
+++ b/src/Symfony/Component/HttpFoundation/RedirectResponse.php
@@ -33,10 +33,6 @@ class RedirectResponse extends Response
      */
     public function __construct($url, $status = 302, $headers = array())
     {
-        if (empty($url)) {
-            throw new \InvalidArgumentException('Cannot redirect to an empty URL.');
-        }
-
         parent::__construct('', $status, $headers);
 
         $this->setTargetUrl($url);
diff --git a/src/Symfony/Component/Yaml/Inline.php b/src/Symfony/Component/Yaml/Inline.php
index 410e23c598..fdd82d91f0 100644
--- a/src/Symfony/Component/Yaml/Inline.php
+++ b/src/Symfony/Component/Yaml/Inline.php
@@ -512,7 +512,12 @@ class Inline
                     case preg_match('/^(-|\+)?[0-9,]+(\.[0-9]+)?$/', $scalar):
                         return (float) str_replace(',', '', $scalar);
                     case preg_match(self::getTimestampRegex(), $scalar):
-                        return strtotime($scalar);
+                        $timeZone = date_default_timezone_get();
+                        date_default_timezone_set('UTC');
+                        $time = strtotime($scalar);
+                        date_default_timezone_set($timeZone);
+
+                        return $time;
                 }
             default:
                 return (string) $scalar;
diff --git a/src/Symfony/Component/Yaml/Tests/Fixtures/YtsSpecificationExamples.yml b/src/Symfony/Component/Yaml/Tests/Fixtures/YtsSpecificationExamples.yml
index d69e97a1a5..ec1c4c3a1a 100644
--- a/src/Symfony/Component/Yaml/Tests/Fixtures/YtsSpecificationExamples.yml
+++ b/src/Symfony/Component/Yaml/Tests/Fixtures/YtsSpecificationExamples.yml
@@ -754,7 +754,7 @@ yaml: |
     Billsmer @ 338-4338.
 php: |
   array(
-     'invoice' => 34843, 'date' => mktime(0, 0, 0, 1, 23, 2001),
+     'invoice' => 34843, 'date' => gmmktime(0, 0, 0, 1, 23, 2001),
      'bill-to' =>
       array( 'given' => 'Chris', 'family' => 'Dumars', 'address' => array( 'lines' => "458 Walkman Dr.\nSuite #292\n", 'city' => 'Royal Oak', 'state' => 'MI', 'postal' => 48046 ) )
      , 'ship-to' =>
@@ -879,7 +879,7 @@ yaml: |
 php: |
    array(
       'invoice' => 34843,
-      'date' => mktime(0, 0, 0, 1, 23, 2001),
+      'date' => gmmktime(0, 0, 0, 1, 23, 2001),
       'total' => 4443.52
    )
 ---
diff --git a/src/Symfony/Component/Yaml/Tests/InlineTest.php b/src/Symfony/Component/Yaml/Tests/InlineTest.php
index 522d77053d..66da12c1dd 100644
--- a/src/Symfony/Component/Yaml/Tests/InlineTest.php
+++ b/src/Symfony/Component/Yaml/Tests/InlineTest.php
@@ -206,7 +206,7 @@ class InlineTest extends \PHPUnit_Framework_TestCase
             array("'on'", 'on'),
             array("'off'", 'off'),
 
-            array('2007-10-30', mktime(0, 0, 0, 10, 30, 2007)),
+            array('2007-10-30', gmmktime(0, 0, 0, 10, 30, 2007)),
             array('2007-10-30T02:59:43Z', gmmktime(2, 59, 43, 10, 30, 2007)),
             array('2007-10-30 02:59:43 Z', gmmktime(2, 59, 43, 10, 30, 2007)),
             array('1960-10-30 02:59:43 Z', gmmktime(2, 59, 43, 10, 30, 1960)),