Allow id's to be used in tables in Admin CP
Closure support for plugins

Plugins can add hooks in the form of Closures to speed up develoment of
smaller plugins.
Removing spacing
Adding support for class methods as well as closures.

Class methods can be passed as an array. You can use either instance or static methods. To use an instance method, consider the following:

    class TestClass
    	{
    		function test($page)
    		{
    			$page = str_replace("<div id=\"content\">", "<div id=\"content\"><p>Hello World!<br />This is a sample MyBB Plugin (which can be disabled!) that displays this message on all pages.</p>", $page);
    			return $page;
    		}
    	}

    	$obj = new TestClass();

    	$plugins->add_hook("pre_output_page", array($obj, 'test'));

 To use a static method, simply pass the class name as the first array parameter and the method name as the second.
Removing stray echo
Adding remove_hook functionality.
Added missing plugin hooks
Adding custom cache rebuild functions
This allows plugin authors to easily include their own rebuild/reload function if they add a cache
Fixes #1860 Wrong message displayed whilst editing user from mod cp
Adds "Can view board when closed" option for usergroups

Completes suggestion from this thread:
http://community.mybb.com/thread-150737-post-1060550.html#pid1060550
change "$bottom_label" type

$bottom_label is "string", it isn't "array"!
Improve collapsed style

Currently if a user was to collapse a table with a thead, the bottom
corners have no boarder radius, but the container does leaving it
looking out of place.
This commit adds the thead_collapsed class to the .thead (if present)
when collapsed or when set as collapsed from a cookie.
new backup file naming scheme: backup__yymmdd_hhmmss_random(.incomplete).sql(.gz)
mysqli optimizations
Merge branch 'feature' of https://github.com/mybb/mybb into feature
Fixing code style of object support for plugins.

Signed-off-by: Euan Torano <euantorano@gmail.com>
Fixes #2280 Hitting Post Thread when having disallowed attachment ignores all submitted content
Fixes #2292 Problem with Find Attachments result in ACP
Fixes #2261 Showing the results of a poll uses theme from post with pid equal to poll's id
Fixes #2278 "You did not enter a description for this scheduled task"