gcc-4.8.x:
 * bump version to [https://gcc.gnu.org/bugzilla/buglist.cgi?bug_status=RESOLVED&resolution=FIXED&target_milestone=4.8.3 4.8.3]
 * refs #1939

download-toolchain:
 * provide gcc-4.8.3 based download toolchain


git-svn-id: file:///var/svn/freetz/trunk@12058 149334a1-2f27-0410-a3b9-fc62619ac1e6