added new plugins folder to repo
first pass at plugin system -- not tested!
tested filter-type hooks, working! :)
sticking to style guide for method names (camelcase)
sending pid as well as content in action:save_post_content hook
added plugins.showInstalled method
sanity check if a plugin's method was not found on hook call
fixed issue where if a hook had no attached methods, it wouldn't work at all... or put simply... nodebb'd break if you had no plugins, heh.
adding admin panel integration to plugins (issue #143)
Merge branch 'plugins' of github.com:designcreateplay/NodeBB into plugins
admin panel integration completion + styling of admin panel plugins page
added note linking to wiki page for authoring plugins... also showing something if no plugins are installed
Merge branch 'plugins'

Conflicts:
	src/posts.js