TODO list for Atlas-C++

Items are in no particular order.

For 0.4.1:
 - remove libsocket++ dependency from tutorial/ (i.e. write a nice,
   _standards compliant_ sockbuf and use that
 - more compiler support without API changes
 - change from .cc to .cpp
 - maybe clean up Net/Stream.cc (without API changes)
 - maybe backport a filter mechanism from 0.5.x if such one should
   exist and prove itself to be stable
 - tests
 - better documentation
 - finish the tutorial