Changes made to pristine jpeg source by mozilla.org developers.

2003/08/18 -- change default mapping for METHODDEF, LOCAL, GLOBAL, EXTERN to better match NSPR

2003/03/14  -- mingw bustage fix. w32api uses different header guard define
               for <basestd.h> than msvc.

????/??/??  -- Lots of undocumented changes. :(