Increment SINGULARVERSION to 3-1-7
Remove generated files from repository
Tweak formatting in src/Makefile.am
Move configure part of 'makesingular*' scripts to separate scripts
Switch fetchsingular to use git repository instead of nightlies

This matches fetchsingular.sw and makes it easier to track the latest
version of Singular.
Fix compilation against spielwiese
Remove some obsolete code
Add a simple README
Remove some obsolete text files
Update my contact details in PackageInfo.g
Fix a minor typo
Correctly use delete[] to deallocate array allocated with new[]