Add support for interactive tools (GxIT)

In theory GxIT should work on dev server with all these changes. a few things:

• I mainly followed https://training.galaxyproject.org/training-material/topics/admin/tutorials/interactive-tools/tutorial.html + a few conf changes from genouest
• I haven't implemented the embedded pulsar runner yet, but we should. I'd just like to test without it first.
• I added things in the jobconf.xml, but I guess it's autogenerated => should I put my stuff somewhere else?

TODO