Pycapnp

- Initial working version of RPC
- Add get_root_as_any to _MessageReader
- Add capnp.pxd for public declarations of cython classes
- Fix problems compiling with gcc4.7

- Change naming of ReaderOption parameters to be pep8 compliant

- Add ReaderOptions to read/read_packed/from_bytes

- Add defaults flag to capnp-json. Also remove 'which' field
- Add capnp-json serializer script. Also fix bugs in from_dict
- Fix build for clang/python3. Also remove -fpermissive
- Add `as_builder` method to Struct Reader
- Add warning when writing the same message more than once
- First working version of capability interfaces
- Wrap InterfaceSchema
- Fix setting string fields to support all types of strings
- Fix changed API for DynamicObject/ObjectPointer

- Add not having installed the C++ libcapnp library to 'Common Problems'
- Add _short_str function for use in capnp_test_pycapnp.py
- Add test script for testing with https://github.com/kaos/capnp_test
- Add handling of DynamicObject
- Fix lists of lists or dicts for from_dict

- Fix problem with to_dict