Sortmerna api

App controller + accompanying unit tests
I'm unsure on how safe is to use this. If I understand correctly, `nr` (in `nr.bursttrie_0.data`) is a user-provided name, right? If that is the case, if the user provides a name with a `.` on it, that would break the code. You can probably first use [splitext](https://docs.python.org/2/library/os.path.html#os.path.splitext) and then use split with `[-1]`. It still can potentially be in case of the `nr.stats` but you can probably create a special case for it