Add support for demo mode in docker. roundup/demo.py Make changes to allow exposed port in docker to be specified separately from the port that demo mode binds to. Also permit bind address specification as well. roundup/scripts/roundup_demo.py: Update required by changes in demo.py. Also move away from positional arguments to prefer flag arguments. Required for passing port and host specification. Flake8 fixes. share/man/man1/roundup-demo.1 Document use of option flags rather than positional params. Other cleanups. doc/installation.txt: Document new docker modes: demo, shell and admin. Update docs: overview section - reorg, added template info for the impatient section - added docker demo mode reference, more docs on top level demo.py use. new section on docker demo mode removed getting roundup section. folded into installing roundup. also prior for the impatient section describes how to download. install via pip in venv recommended supported method document all provided templates. not just minimal and classic. added index references. move sections around, decreased sectin depth, reformatting scripts/Docker/roundup_healthcheck: When running roundup-demo, there is no tracker spec. So default to demo if no tracker=directory args found. Prevent's docker from reporting an unhealthy container when running demo. scripts/Docker/roundup_start: implement demo, shell, admin docker modes.

This directory has some detector examples that you can use to get
ideas on implementing your own detectors.

These are provides on an as-is basis. When they were added, they
worked for somebody and were considered a useful example.

The roundup team will attempt to keep them up to date with major
changes as they happen, but there are no guarantees that these will
work out of the box. If you find them out of date and have patches to
make them work against newer versions of roundup, please open an issue
at:

   https://issues.roundup-tracker.org

The current inventory is:

creator_resolution.py - only allow the creator of the issue to resolve it

emailauditor.py - Rename .eml files (from email multi-part bodies) to
                  .mht so they can be downloaded/viewed in Internet Explorer.

irker.py - communicate with irkerd to allow roundtup to send announcements
           to an IRC channel.

newissuecopy.py - notify a team email address (hardcoded in the script)
		  when a new issue arrives.

newitemcopy.py - email the DISPATCHER address when new issues, users,
                 keywords etc. are created. Kind of an expanded version
		 of newissuecopy.