- use correct 'mingw-w64' package name
- small grammar fixes
- modify Cygwin build instructions to use that same compiler as well: the
original mingw is stuck at gcc v4.7 and does not seem to be updated anymore
- make it clear thet uPy also builds using Visual Studio versions > 2013
Ubuntu's mingw32 has gcc 4.2.1, which is rather old and has incorrect
non-initialized variable analysis which produces warnings, which
per MicroPython default settings get turned into errors.
stijn
Paul Sokolovsky