Add create_dmd_release utility.
delete-trailing-whitespace
print help message if invoked without arguments
don't clone over SSH
remove dependency on external zip/7z tools

- use std.zip for archiving and extracting
- rename --archive-zip option to --archive
  and --combine-zip to --combine
Merge pull request #2 from MartinNowak/create_dmd_release

create dmd release
Merge pull request #24 from Abscissa/create_dmd_release

Add create_dmd_release utility.