gnucash-on-windows master: added optional argument of setup_mingw64.ps1 to existing MSys2 environment

[Geert Janssens]

Updated	 via  https://github.com/Gnucash/gnucash-on-windows/commit/c7669b05 (commit)
	from  https://github.com/Gnucash/gnucash-on-windows/commit/4e815447 (commit)



commit c7669b055f356d95bfdebc43c3df89aafd07eeb3
Author: Jannick <thirdedition at gmx.net>
Date:   Mon Dec 25 22:30:39 2017 +0100

    added optional argument of setup_mingw64.ps1 to existing MSys2 environment



Summary of changes:
 setup-mingw64.ps1 | 30 +++++++++++++++++++++---------
 1 file changed, 21 insertions(+), 9 deletions(-)