Generate new contributing files

[doowb]

Currently, this updater only moves contributing files from the root to a .github directory. I'd like to be able to generate the contributing files if they don't exist.

I'm thinking of adding generate-contributing here as a sub-updater that can be used for generating the contributing files.
Some modifications will need to be made to generate-contributing so updater-contributing doesn't have to use workarounds to try to include the generate features that generate-contributing expects.

Is this a good idea to include in the updater?

[jonschlinkert]

I made some major updates to this, I'll be pushing them up soon. I'm trying to fix some underlying issues first