Chapps

- correcting import of test library feature into main codebase

- adding more comprehensive CHAPPSException handling

- correcting packaging error which prevented installation of
dependencies

- removing static SystemD service profiles from pip package; they
remain in the repo, for use via git clone.

- correcting fatal bug wherein receiving email with a null sender
would cause the application to crash. It is now possible to
specify for each policy whether null senders are "ok"; the
default is False.

- bug fixes: due to poor design choice, all policies in a
multipolicy handler will end up with the same config, that being
the config for the last configured policy. As such, earlier
ones would send the wrong messages, and possibly exhibit other
problematic issues. This is fixed.

- OQP default acceptance response changed from OK to DUNNO

- ConfigParser instructed not to perform interpolation on INI
file, in order to allow all arbitrary garbage (for passwords)

- handlers now provide property methods to obtain the appropriate
listener address and port numbers

- putting extra artifacts in a chapps dir, w/i venv or /usr/local
depending on whether a venv is used

- Updating documentation