Sub cache auto maintenance, minor style fixes, revision bump

[arvvoid]

Please check that your pull request pass this checks:

• [x] My changes respect the Kodi add-on development rules
• [x] My code is both Python 2 and 3 compatible
• [x] My code follows the code style of this project (PEP8, long lines allowed if make sense)
• [x] I made sure there wasn't another Pull Request opened for the same update/change
• [x] I have successfully tested my changes locally

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Adding a new region/hbo go version

Description:

This pull request adds subtitle cache autocleaning and manual subtitle cache cleaning from the advanced setting menu. Revision bump Style fix for import translatePath