Monthly (by day of month) not working on short months

Opened the issue related to this PR on https://github.com/seejohnrun/ice_cube/issues/191

I have never got hands on ice_cube, so the first step to fix the issue was right the test to cover regression.

So opened this PR with tests then we can discuss or (if luckly) I code the solution, then I update here ;)

**not ready to merge yet**

Thank you