Fix 'Unknown CMake command "razor_translate_ts"' error.

This error message is produced by configuring with -DSPLIT_BUILD=On -DMODULE_GLOBALKEYSHORTCUTS=On:

-- Found Qt4: /usr/bin/qmake (found version "4.8.4") 
CMake Error at razorqt-globalkeyshortcuts/config/CMakeLists.txt:113 (razor_translate_ts):
  Unknown CMake command "razor_translate_ts".