Feature: Fix a target directory's namespace usage based on the map file

When converting a repo from ZF1 to ZF2 per the manual it's advised to not change change the Controller initially only the model classes. The problem is how do you change the references in your Controller classes so that they adhere to the transformation done with the namespacer tool.

Proposed solution:

Add new command called `fix` that takes as input map file and target directory. The command will use the map file to replace all references of the old namespace format with the new one.