Carles/ng restructure

This is a superset of https://github.com/pretenders/ployst/pull/66

It includes a major overhaul of the angular project structure, more in line with some best practices (e.g. [Google's](https://docs.google.com/a/gagnavarslan.is/document/d/1XXMvReO8-Awi1EZXAXS4PzDzdNvV6pGcuaF4Q9821Es/edit)). This will make the project more maintainable as it grows. It is only a first step, I haven't split things out like controllers and directives etc.

I've made it a separate PR because this is more unreadable than the other one. Feel free to close #66 if you prefer to merge this one directly.
We are not using this ATM, it will become useful when we include things like global provider configuration. We might as well get rid of it.