Custom CSS tweaks for Firefox v4.1.7

Full changelog: https://github.com/Aris-t2/CustomCSSforFx/commits/

[GENERAL]

• Fx100+: workaround for :-moz-lwtheme-darktext and :-moz-lwtheme-brighttext removal

[General UI]

• (fix) Win7/8: 'page context menu > back, forward, reload and bookmarks button labels + icons'

[Buttons]

• (tweak) custom back/forward buttons appearance > connected to location bar

[Location Bar]

• (tweak) identity box colors
• (tweak) popup > hide 'Search with...' and 'Visit...' results

[about:preferences]

• (fix) alternative appearance