Bump cartola to 0.12.
Bump cartola to 0.12.

This will fix the pyyaml conflict as we're using the one defined
by cartola.

Also fixed the crypto import issue on windows.

Fixes: #338

candango/firenado,piraz/firenado,candango/firenado,piraz/firenado,candango/firenado,piraz/firenado