Added imgur history feature

Fixes #165
Tabs=Fixed?

Title now updates correctly, as do recent files and history. woohoo!
Fixes #81
Added extension filters for all supported filetypes

should have did this in the last commit
.mapinfo and .campaign backend
Merge branch 'master' of https://github.com/XboxChaos/Assembly
Whoops closing undocked tabs makes the active content null

tabs=more fixed lol
how about some drag n drop
Merge remote-tracking branch 'origin/master' into tag_block_editor