getwinegit.sh 0.21 released

[Christian Lachner]

Hellooo, punctual to the new wine-0.9.9-release there is a new version
of my getwinegit.sh-script. No great changes but some smaller ones.
First of all, the logger got more informative if you experience
problems with your getwinegit.sh-installation. The second thing is a
better checking of the config-vars. Not the supergreat errorhandling i
would like it to be but now there is something that checks if the vars
are set and so on. The last thing is that the readme got a bit more
informatical (dependencies and compatibility of shells). Maybe there
were some more minor changes in the script but... i can't remember ;).
Current version is now 0.21.

PS: the release is now packed in a tar.bz2 as requested :D