Fix docstring formatting & set private members about foca

[kushagra189]

@uniqueg should I go ahead with this recommended styling for docstrings?

[kushagra189]

@uniqueg can you elaborate what all methods are private? Also, the idea is to hide them and not document within the docs?

[uniqueg]

Never really saw that comment @kushagra189: I think we would want to "hide" everything that the users don't really need. So what do they need to know about:

• foca.foca.foca() function: to understand the main entry point into FOCA
• foca.models.config module: to understand how to write the config file
• foca.utilities subpackage: to see what useful functions they can import and reuse

I think everything else can be skipped from the API docs. As for how to skip them: I would probably not completely hide them, but change the table of contents in API docs so that only these are visible from the start. It would probably still be good to leave everything else in, perhaps under a link "complete API documentation" or so, as it is still useful for FOCA developers (and sometimes app developers, too, if there are some bugs/issues).