mingw-w64-gcc - 6.3.0 - Update to latest version
mingw-w64-gmp - 6.1.2 - Update to latest version
mingw-w64-mpc - 1.0.3 - force rebuild
mingw-w64-mpfr - 3.1.5 p1 - Update to latest version and use p1 patch
mingw-w64-windows-default-manifest - 6.3.4 - Update source location. The old CVS no longer exists.
* upgrade some broken packages
* correct some broken urls/checksums
* use secure urls where possible
* update PKGBUILD templates
* remove line-ending whitespace
* minor typos/fixes
Remaining md5sums either didn't download or
didn't pass checksum tests.