Publish PROTEUS to PyPi

[timlichtenberg]

As suggested by @lsoucasse, one of the next steps is to push PROTEUS to be published on PyPi. Before that, we need to resolve the following issues:

• [ ] #236
• [ ] Aragog #6 Converting data tables from entropy to pressure
• [x] #267
• [x] #269
• [x] #263