More non C89 compliant comments
Added SDL_assert_always (never disabled).

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extra : rebase_source : ff08944ae7b6f86458840f29a3bf82ccb89b0307
Added SDL_DEPRECATED #define.

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extra : rebase_source : 865047af634b49c9f5101656e1055d0278720633
Fixed cut-and-paste error.

--HG--
extra : rebase_source : 95c9c82bc324e35b10e4f3a5199c792d06d71f5b
Added SDL_GetBasePath() and SDL_GetPrefPath() in new filesystem module.

--HG--
extra : rebase_source : c1fac232063443a2880e64f1abda85e0bdb2e710