add useful variables for non-Makefile generators to set where we want our stuff built
use SDL_Threads everywhere
The trick was to mark the threaded functions as cdecl and load arguments correctly. This allows us to:
- drop a few ifdefs;
- use integrated waiting code;
- remove some whitespaces \o/;
- fix
bug #591.
small engine translation updates. Thanks to community members 'Wuzzy' and 'Flandre Scarlet' for their suggestions :)