Folder structure

[dclow]

We need to figure out a better folder structure for the files.

I recommend something like having the files that actually have HARK in their name in the main folder. ConsumptionSavingsModel.py can be in a folder called "ConsumptionSavingsModel", the DAP model can be in a folder called "DAPModel", etc.

[dclow]

Started this process by merging in the "folders" branch, but there is still much more work to do

[mnwhite]

Folder structure is now where it should be for beta release. Files in /Testing need to be slightly edited to fix paths.