Crycompare

Update setup.py. Now available on pypi repo via `pip install crycompare`. Updated README.md accordingly.

Code organized as package, price and history separated in two files.
Minor fixes made, but code is pretty much the same.
Requests calls now return only data, without status codes and messages.

Classes Price and History added for wrapping CryptoCompare public API.
Both classes return type 'dict' from parsed json objects. See documentation for classes' methods.