Add msys-coreutils-ext package

The command seq included in this package is required by mgwport.

Signed-off-by: Thomas Braun <thomas.braun@virtuell-zuhause.de>
Merge branch 'master' of https://github.com/sschuberth/mingwGitDevEnv
Add missing space at end of package

which was forgotten in d6b04c0f5fee625f344a2123f90d98c4d1c955ba.

Signed-off-by: Thomas Braun <thomas.braun@byte-physics.de>
Merge branch 'master' of github.com:t-b/mingwGitDevEnv