lupdate-qt4/lrelease-qt4

apply variable change here as well

on linux assume datapath is always relative to cmake_install_prefix, unless you provide an absolute path; on win32/osx hardcode engine path to default installation prefixes (it gets overridden at runtime so it works even if you move the data folder)

Oops, forgot this check (fixes crash)

typo and doc

fix file association on windows too

use rev info from the just created file when configuring without mercurial

dump rev and hash in a file to be packed by cpack

adjust cpack ignored files (libraries, mobile project files and win res files are still necessary)

hopefully fix bug #523, file extension association