Upgrade Ruby 2.1 series for Travis
Fix conforming to Jekyll's StaticFile API from 1.5.0
Rename method to have more accurate name
Rename variables and parameters to have more accurate names
Remove leading path from asset bundling log messages

Cleaning log output.
Use safe_yaml to load user input from minibundle block

This is what Jekyll uses internally to load YAML input. It's good idea
to use it here as well for consistency and safety.