Rewrite SMTP Notifier to use MIME::Tools (instead MIME::Lite)
Add API call for sending notification, add testmail for smtp

The api method send_notifcation allows for triggering the notification
backend to send a preconfigured notification. A testmail is included in
the config set to allow easy testing of the smtp setup.
Add a first draft oft openxpkicli binary as simple command interface

The openxpkicli offers a simple interface to the openxpki api to execute
arbitrary commands. Needs further testing and improvement.
See perldoc for usage details.
Refactoring of Workflow Factory to match the patched upstream version

Replace the workaround of the wrapped workflow class by the features
invented by our upstream patch on Workflow.pm.
There is still a bug in 1.35_1 upstream so we depend on the 1.36 which
will hopefully include the necessary fix.
Add autofail option to workflow activity, add some more docs on workflow

The action definition within the workflow description accepts the flag
autofail="yes" which causes the workflow to be moved to the FAILURE
state and marked as finished.
Terminate watchdog if main server crashed (+ minor SMTP fix)

Fixes #25
Complete code for autodiscovery of token configs #24

Move the inheriting config to a new method in OXI::Config
Implement resolving of aliases to group names and using it to fetch the
token config based on groups.
Preliminary fix for issue #27, needs testing with nCipher engine settings