## 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**
* Initial revision of fail2ban sensor
* Verified working, added tests
* Re-factored code so that log reading isn't called for each sensor
* Lint fixes
* Removed errant reset of last ban, added test to verify bans persist through update
* Removed for loop in read_log and replaced with regex per review request
* Refactored update to use current ban array for last ban state
- also was missing return False in timer for default behavior
* Removed CONF_SCAN_INTERVAL from PLATFORM_SCHEMA.extend
- renamed DEFAULT_SCAN_INTERVAL to SCAN_INTERVAL
* SCAN_INTERVAL changed to timedelta
* Force travis rebuild (last build timed out)
* Using compiled regex now
Ville Skyttä
Paulus Schoutsen
Kevin Fronczak