Applying consistent default window behavior across platforms.

Now all windows open in a border as opposed to fullscreen. blender -W restores
old functionality, blender -w is now default. This lets each platform's window
manager deal with it's own issues.

As per issue 6391 in the patch tracker.

Changing some default link flags, crossing fingers and waiting for bugs to
magically be fixed.

Patch by fab31 not to clobber SDL audio environment variables if they're
already set.

Correcting order for static linking.

Reordering OpenEXR libraries to correctly reflect dependencies.

This fixes some ld errors when the static versions of the EXR libs are used.

Build system - Bug Fix/Cleanup: Moving use_fluidsim variable to platform specific section where it belongs as per ML and IRC discussion. This allows platform maintainers some flexibility in determining what should be compiling on each system. Right now fluidsim is set as true everywhere and there is no functional change from before.

Modifications for bullet were made and variables were defined only for windows. This commit defines these variables for the other blender platforms helping SCons not to barf quite as quickly. Scons is still unable to compile a fresh CVS checkout at the present time on linux, but now at least allows config.opts to be properly created.

The new defines for use_bullet are currently set as false until testing can take place to ensure proper compilation on those systems. The existing use_bullet='true' on the windows platform was left untouched.

Please ensure that variables are defined on _all_ platforms in the future instead of just defining them for the system you're currently developing under.