one-liners need should
Failing spec for minor
Only print minor if set
Failing spec for = 1 -> 1.0.0
If not using pessimistic operator, set nil minor and patch to 0
identify operator by type and not comparison function
add additional test for initialization
Merge pull request #17 from RiotGames/constraint_strings

If not using pessimistic operator, set nil minor and patch to 0