Doc fixes

Hi o9000, thanks for resurrecting tint2!

Here are some purely "bureaucratic" fixes: I fixed some typo's, updated URLs, and cleaned up a few files.

See merge request !4

Clean up .desktop file: remove unnecessary localization, fix English translation, use consistent captitalization of "tint2" (with a lowercase "t").

tint2: Do not rely only on select() to detect new X events, since we sync the socket in the system tray which messes up select

systray: (disable_transparency=1) detect empty icons whenever a new icon is added, from any process; clear icon area because some icons were failing to redraw

systray: fix black icon background for 32-bit icons when disable_transparency = 1; fix empty icon detection when disable_transparency = 1; fix icon blinking by delaying rendering less aggressively; removed XClearArea on traywin->win (triggers unnecessary redraws); cache icon names; profiling messages updated

systray: Profiling code. Export environment variable SYSTRAY_PROFILING=1 when running tint2 to enable it

tint2conf: added bs, hr and sr translations

I translated tint2conf into Bosnian, Croatian and Serbian (Cyrillic).

See merge request !3