Malformed version number string 0.7-SNAPSHOT

Rake does not like the letters in the version in the Rakefile.
git clone http://github.com/codeaspects/ruleby.git
cd ruleby
rake -T
(in /Users/ric/code/ruleby)
rake aborted!
Malformed version number string 0.7-SNAPSHOT
/Users/ric/code/ruleby/Rakefile:17

Removing the -SNAPSHOT fixes the rake.
