## Description:
More fixes flagged by pylint 2 that don't hurt to have before the actual pylint 2 upgrade (which I'll submit soon).
## Checklist:
- [ ] The code change is tested and works locally.
- [x] Local tests pass with `tox`. **Your PR cannot be merged unless tests pass**
* Added support to Yahoo Finance to track the stock market within Home Assistant
* Fixed pylint issues
* Fixed formatting issues
* Fixed pep257 issues
* - Fixed URL link
- Added attributes for Yahoo Finance
* Removed price sales ATTR
* Fixed lint and flake8 issues. Added attribution to Yahoo! per https://developer.yahoo.com/attribution/