Break up stream code to use separate notice stream classes

Rearchitect (again!) notice stream code to delegate different functionality up and down the stack.

Now, different classes implement NoticeStream.

lib/repeatsofmenoticestream.php

@@ -0,0 +1,59 @@
+<?php
+
+class RepeatsOfMeNoticeStream extends CachingNoticeStream
+{
+    function __construct($user)
+    {
+        parent::__construct(new RawRepeatsOfMeNoticeStream($user),
+                            'user:repeats_of_me:'.$user->id);
+    }
+}
+
+class RawRepeatsOfMeNoticeStream extends NoticeStream
+{
+    protected $user;
+
+    function __construct($user)
+    {
+        $this->user = $user;
+    }
+
+    function getNoticeIds($offset, $limit, $since_id, $max_id)
+    {
+        $qry =
+          'SELECT DISTINCT original.id AS id ' .
+          'FROM notice original JOIN notice rept ON original.id = rept.repeat_of ' .
+          'WHERE original.profile_id = ' . $this->user->id . ' ';
+
+        $since = Notice::whereSinceId($since_id, 'original.id', 'original.created');
+        if ($since) {
+            $qry .= "AND ($since) ";
+        }
+
+        $max = Notice::whereMaxId($max_id, 'original.id', 'original.created');
+        if ($max) {
+            $qry .= "AND ($max) ";
+        }
+
+        $qry .= 'ORDER BY original.created, original.id DESC ';
+
+        if (!is_null($offset)) {
+            $qry .= "LIMIT $limit OFFSET $offset";
+        }
+
+        $ids = array();
+
+        $notice = new Notice();
+
+        $notice->query($qry);
+
+        while ($notice->fetch()) {
+            $ids[] = $notice->id;
+        }
+
+        $notice->free();
+        $notice = NULL;
+
+        return $ids;
+    }
+}