Initial check in of PXE Manager
Address comments from @viglesias
- created global dict for distros
- instead of iterate over key/valkue pairs and  just use directly. (I had originally used the same methodology when dealing with more than one key/value pairs)
Basic functionality for making a reservation and actually doing the work on the backend (cobbler).
Free machines implemented

Updated the machine schema

Added find_resource method to client to allow querying machines by any field
1. Made cobbler server url, user and password configurable
2. find_resource renamed to find_resources to better reflect what is returned which is a json of the query submitted. Also added request checking to the method to be consistent with the other request methods.
Merge pull request #3 from tbeckham/master

Initial check in of PXE Manager