load q2 game dlls from the binarydir in preference to gamedir (allows such dlls to be distributed with the engine).
add small emscripten msvc project so I can build the web port a little more conveniently.
require mouse releases to have had a corresponding mouse press while in the menu. this solves issues with mouse clicks triggering the load menu while dead and instantlyish loading one, and alt-tab issues too.
git-svn-id: https://svn.code.sf.net/p/fteqw/code/trunk@4755 fc73d0e0-1445-4013-8a0c-d673dee63da5
