Consolidate TTS cache logic

[chrisveilleux]

Description

The impetus for this change is an attempt to fix an issue with pre-loaded cache files on devices that use Mimic2.

• Consolidate all the logic dealing with TTS caching into a single module.
• Replace logic that copies persistent cache to temporary cache with logic that checks both places

How to test

Check that persistent cache files are not in /tmp and still get used when requested.

Contributor license agreement signed?

CLA [Y]

[pep8speaks]

Hello @chrisveilleux! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2021-03-11 03:16:44 UTC

[forslund]

Looks really good. Great to get rid of the copy from persistent cache to the tmp one.

I noted two things (one that is an iseue, and one that may just be me not quite grasping the idea)

[devops-mycroft]

Voight Kampff Integration Test Failed (Results).
Mycroft logs are also available: skills.log, audio.log, voice.log, bus.log, enclosure.log

[devops-mycroft]

Voight Kampff Integration Test Failed (Results).
Mycroft logs are also available: skills.log, audio.log, voice.log, bus.log, enclosure.log

[devops-mycroft]

Voight Kampff Integration Test Failed (Results).
Mycroft logs are also available: skills.log, audio.log, voice.log, bus.log, enclosure.log

[devops-mycroft]

Voight Kampff Integration Test Failed (Results).
Mycroft logs are also available: skills.log, audio.log, voice.log, bus.log, enclosure.log

[devops-mycroft]

Voight Kampff Integration Test Failed (Results).
Mycroft logs are also available: skills.log, audio.log, voice.log, bus.log, enclosure.log

[devops-mycroft]

Voight Kampff Integration Test Failed (Results).
Mycroft logs are also available: skills.log, audio.log, voice.log, bus.log, enclosure.log

[devops-mycroft]

Voight Kampff Integration Test Succeeded (Results)