Turns out you need to name the compiler gcc for things to work out, BUT
clang never knows how to compile ada ANYWAY, so it *will* turn to gcc to
try to compile it.
*however* it calls gcc by name, so in this case, it calls... itself recursively
until it goes boom.
Plain disable the ada test..
- get rid of libtool and thus rpath bugs
- install libexec files as they're also needed
- copy the crt files in lib/gcc/i386-mingw32/3.4.5 as the
compiler looks for them in there and not in lib
- disable shared and thus lose the platform specific files
(noticed by jeremy@ as well)
- adapt the README after these changes
