restore launch.sh testing in appveyor

[romani]

from #201

configuration was removed to unblock PR acceptance process.
We do not use launch.sh now actively, as there is groovy variant of it.

[rnveach]

I upgraded cygwin to the latest (2.879) locally and launch.sh has no issue running as is.
Could failure before have been a bug in cygwin (2.877)?

2.877 is still in build logs at https://ci.appveyor.com/project/Checkstyle/contribution/build/456/job/9h9kn96u7jil5lpk#L47 .

[romani]

Could failure before have been a bug in cygwin (2.877)?

most likely ... can we upgrade to new version at appveyor ? might be possible to file issue against appveyor to upgrade.

[rnveach]

I recommend closing this as we are not going back to SH scripts and use groovy.