all use is_open
split cybin cython code to transport and protocol

more cleaner code structure
refactored cybin code
Merge pull request #32 from eleme/cython_buffered_transport

rewrite cybin protocol
handle exception in cython functions
Merge pull request #33 from maralla/cybin_handle_exception

handle exception in cython functions
include cytransport in MANIFEST.in
unify trans_factory naming for client

transport_factory -> trans_factory
c_read_struct should return result object
Merge pull request #34 from maralla/read_struct

c_read_struct should return result object
add makefile development helper
add changelog, version bumps to v0.1.9