[services] Expose services exposed by robots in details request

Part of #299
[pymorse] Export robot services as method

Fix #299
[doc] Added a favicon to MORSE documentation
Add subparsers for MORSE sub-commands

This allows to cleanly support different set of
cmd-line options for sub-commands like 'run', 'edit', 'check'.

This is a required cleaning step before introducing 'morse create'
family of options.