Yosemite text field.

Nothing in commit should break Mavericks, but I have no way of testing right now
Disable vibrancy until list views have been refactored
Redefine under what circumstances the main window is considered active.

Considered active now as long as isMainWindow is matched instead of key window.

Just a dirty fix in preparations for list rewrites.
Completely rebuild message archive storage mechanism
No longer display inline images when reloading history
Fix truncation logic
New rainbow icons
New icons
New icons
Fixes #452 submitted by @jpnurmi

Also redesigns some internal workings of client capacities to put them
in their own struct for easier management.
Cache timestamp of server-time under certain conditions
Slightly modified logic
Merge branch 'pr/12'

Conflicts:
	Classes/Headers/IRCClient.h
	Classes/IRC/IRCClient.m
	Classes/IRC/IRCMessage.m