nnesse/minwin-gcc-5-2: A patched gcc 5.2 enabling a new 'minwin' target that does not link to the Microsoft C library.

Niels Nesse eb72d50f44 Import gcc 5.2.0 from tarball		9 éve
..
reader.go	eb72d50f44 Import gcc 5.2.0 from tarball	9 éve
reader_test.go	eb72d50f44 Import gcc 5.2.0 from tarball	9 éve
writer.go	eb72d50f44 Import gcc 5.2.0 from tarball	9 éve
writer_test.go	eb72d50f44 Import gcc 5.2.0 from tarball	9 éve