Modify modulesync config to create symbol keys instead of strings

By default yaml keys are strings instead of symbols.
In the code symbol keys are used which cannot be merged correctly
This PR adds a Hash function to convert keys into symbols.
This way the yaml file can be standard like all other yaml files with this project
Merge pull request #1 from electrical/config_keys_to_sym

Modify modulesync config to create symbol keys instead of strings