Frontend: Fix built-in Qt translations not loaded properly

Update INSTALL.md about new Qt5 dependency

Fix buggy Qt5 style detection causing segfault on Arch Linux w/ qt5-style-plugins

try plastique with fallback to windows - we should find a way to alert the user that qt5-style-plugins would improve rendering

seems to help styling some - some CSS tweaks may still be needed - lobby for example

Update .hgignore to ignore new Qt's moc_ and qrc_ files

Also update default binds for SDL2 keypad names

these changed, presumably in SDL2 - might want to review all the others

Use visible team count instead of total team count to determine rendered team bar height

Remove rubber duck from BRW, RW and most weapon schemes for now The duck is not liked by players. Rubber duck needs a lot of rework. Before that happens, better remove it from game modes for now. Players can always modify the weapon schemes, of course.

Use onSkipTurn in scripts to detect turn skips

Lua API: Add onSkipTurn callback, called when hog skips

Lua API: Add SkipTurn() to replace ParseCommand("skip")

ACF7: Add one pick hammer in crate Players often reported to screw up with the pick hammer, which is quite annoying. With one pick hammer more, this mission should be slightly less annoying.