[WIP] Add public service api

[remimarenco]

As discussed together, we think adding Public Servers CloudLaunch could be a good idea. Here is the implementation during GCC Coding Hackathon.

xref: bxlab/galaxy-hackathon#20

[afgane]

Overall, looks good but missing a migration file (it'll be in migrations/0006_... or similar)

[remimarenco]

Hrmmm ok I removed the migration folder thinking it would not be necessary (thought makemigration + migrate would do the trick in any configuration).

So should I push all my migrations then? Even if they are polluted with tests migrations / errros?

[nuwang]

I think the easiest thing would be to delete all migration files except for the ones already in github, and then run makemigrations, which will create a squashed migration file. Then push that in.