mark UNIX scripts as executable


git-svn-id: svn://svn.code.sf.net/p/mediainfo/code/MediaInfoLib/trunk@6496 45c5ae6f-87cc-4fd0-92ee-e4f023fd80da
gnu/makefile: install headers


git-svn-id: svn://svn.code.sf.net/p/mediainfo/code/MediaInfoLib/trunk@6497 45c5ae6f-87cc-4fd0-92ee-e4f023fd80da