Started with implementing Goodbye Spammer

Note: It's very likely that this isn't working as it's a direct port till now and not tested.
ToDo:
Settings and Template names need to be added to the language files
moderation.php needs to be checked
templates need to be cached
templategroup need to be added while upgrading
general code check
Fixed a few issues introduced with the last commit

added template group to the language file
optimised moderation.php
added templates to the templatecache
templategroup is now added while upgrading
Merge branch 'upstream/feature'

Conflicts:
	moderation.php
	showthread.php
Including https://github.com/MattRogowski/Goodbye-Spammer/pull/1
Changed checkboxes to hidden fields
Renamed "goodbyespammer" to "purgespammer". Also removed the (new) templategroup and moved the templates to the "moderation" templategroup
Merge branch 'upstream/feature'
Fixes a few issues introduced with the last commits
Use the new get_input method instead of accessing the variables directly
Fixes #319 Searching thread prefix only searches one prefix even if multiple selected
Coding standards
Fixes #353 Inline moderation selection lost on "select all"
Fixes #367 Inline Moderation CheckAll notice remains ...
Fix #258 Stick Thread checkbox is not checked by default
Top referrer

https://github.com/mybb/mybb/issues/434
Top Referrer

Coding Standards correction.
Fixes #658 Super Admins doesn't work as expected
WIP #435 Moderation Tools Improvements
fixsavecopy
Fixes #700
fixvideopath