intelmqsetup: Support for intelmq-manager

https://github.com/certtools/intelmq/blob/develop/intelmq/bin/intelmqsetup.py currently supports the IntelMQ Core and the API. Support for the Manager shall be added.

The installation of the Manager is currently tricky and has flaws.

• On wheel/sdist build, the HTML files are generated, the files also contain the sources
• pip can't install the html files to the correct location, they land in /usr/local/lib/python3/
• the destination directory is not fixed, it depends on the distribution (just like with the API files)

This is not good usability. Installation via deb/rpm packages or docker is recommended, but not limited to them.
With our own installation method, we can fix the above issues.

There's one disadvantage: When the build happens during installation, the build dependencies need to be installed. As the user used pip anyway, installing mako as dependency is OK.