This adds a requirement for all definitions that have foreign keys to also
require indices for all source (local) attributes mentioned in foreign keys.
MariaDB/MySQL creates indices for source attributes automatically, so this
serves as a way to get rid of those automatic indices and create clean explicit
ones instead.
In PostgreSQL, most of the time, indices on the source are necessary to
decrease performance penalty of foreign keys (like in MariaDB), but they aren't
created automatically, so this serves to remove that difference between
PostgreSQL and MariaDB.
This will look for and load files named 'ExamplePlugin.php' or
'Example/ExamplePlugin.php' either in the plugins/ directory (for
plugins that ship with StatusNet) or in the local/ directory (for
plugins you write yourself or that you get from somewhere else) or
local/plugins/.
Plugins are documented in their own directories.
Additional information on using and developing plugins can be found
at the following locations:
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