Merge branch 'release/0.3.7' into develop
Finish up adding docstrings to all public classes/methods
Add full orphan functionality. Also, allow special orphan lists

that can grow over time.
Change orphan list semantics a bit
Add some useful _StructSchema, reader, and builder methods

This adds:
 - _StructSchema.fieldnames
 - _DynamicStructBuilder.as_reader
 - _DynamicStruct{Reader,Builder}.schema and __dir__

This makes the reader and builder types much easier to navigate in ipython.
Expose _StructSchema's raw node
Add testing libraries to requirements.txt
Merge branch 'master' of https://github.com/amluto/capnpc-python-cpp into develop

Conflicts:
	capnp/capnp.pyx
	capnp/capnp_cpp.pxd
Update docs for developers
Fix change in C++ API of deleted default constructors for builders
Lowercase schema so it conforms to member naming conventions
Add _capnp for original Cython module. Meant for testing.
Add initial tests
Fix tests
Update travis to use tests
Add regression test
Bump version for v0.3.8
Merge branch 'release/0.3.8'