Support for SPARC, PPC(GCC), zLinux and zOS

I've added support for
Sparc 64 on Solaris with GCC
PPC 64 on AIX with GCC
zLinux 31/32 and 64 (with GCC)

I've also added support to mintomic for zOS (amode 31 only, 64 would be easy from here) compiled with xlc. The mintsystem and mintpack support isn't really complete, just enough to run the tests, and I don't have cmake for zOS (I couldn't compile it in a sane amount of time) so there is a shell script as a workaround for me.