- Replaced the sound browser by a completely new one.
  - It's much faster and has more features.
  - It got a favourite manager added
- Added wire_filebrowser and wire_listeditor VGUIs.
- Adjusted the wire_expression2_browser to use GMod 13's docking.
Added some functions (for sound browser's favourite manager).
- Added the common sounds from the GMod wiki as sound list.
The files addon.txt and icon.tga aren't no longer needed in GMod 13+.
(Source: http://garrysmod.com/post/44073908112/gmod-update-158 At "Legacy Addon Mounting Changes")
Merge pull request #262 from Grocel/master

New better, faster, stronger Sound Browser!