Add cli for finding locations of registered func

[victorialslocum]

Description

Add cli command for finding the locations of registered functions. Required function argument, optional registry name argument. Provides a local file link and line number for the function.

$ python -m spacy find-loc spacy.TextCatBOW.v2
Found registered function at file:///Users/.../spacy/ml/models/textcat.py:92

$ python -m spacy find-loc spacy.Corpus.v1 readers
Found registered function at file:///Users/.../spacy/training/corpus.py:22

Types of change

New cli feature

Checklist

• I confirm that I have the right to submit this contribution under the project's MIT license.
• I ran the tests, and all new and existing tests passed.
• My changes don't require a change to the documentation, or if they do, I've added all required information.

[victorialslocum]

Wasn't sure if we also wanted to put this in the docs or not, let me know if so and I can update that!

[adrianeboyd]

find-function?

[svlandeg]

I think this is neat :-)

$ spacy find-function spacy.TextCatBOW.v1 -r "architectures"
✔ Found registered function at
...\lib\site-packages\spacy_legacy\architectures\textcat.py:41

$ spacy find-function spacy.TextCatBOW.v2 -r "architectures"
✔ Found registered function at
...\spacy\ml\models\textcat.py:92

[rmitsch]

Looks good!

[adrianeboyd]

Looks good to me, thanks @victorialslocum!