This is necessary to properly upgrade the package dependencies when
installing the new versions of the packages themselves and fixes the
problem with the new Python 2.7.14 failing to run since its package was
updated from 2.7.13.
This doesn't work any longer since Cygwin Python 2.7.14 update, see
https://cygwin.com/ml/cygwin/2017-11/msg00053.html
Avoid using it by preventing include/wx/stc/stc.h file from being
updated, this shouldn't be necessary anyhow as the version in git should
be already up-to-date.
Disable more libraries and use --disable-optimize instead of --enable-debug
(also for MinGW) as we don't really need debug information in these builds and
not generating it might make things faster.
