[AdBlock] Don't add domain css rules to sites whitelisted with $document option

Closes #1246
Fixed, renamed QupZilla class to BrowserWindow everywhere
[Code] Little cleanups after rename QupZilla -> BrowserWindow
[Code] Renamed qz_namespace.h to qzcommon.h
[Scripts] generate-translations now generate also .qrc lines
[Code] Moved history menu into separate HistoryMenu class