Now special characters are allowed in db passwords

Since the db passwords in `database.yml.erb` are not enclosed in
single quotes, passwords like `@wow!such$ecure%doge` will fail
because they are not escaped properly. Just enclosing the db
passwords with single quotes fixes the problem.
Updated spec test cases
Merge pull request #123 from tPl0ch/hotfix-db-pw

Now special characters are allowed in db passwords