Tracking issue for Qei trait

[eldruin]

The Qei trait available on the 0.2.x versions has been removed ahead of the 1.0.0 release. See: #357
This issue servers as a tracking issue until we add it back. The open (breaking) problems should be reasonably-well solved and all associated types should have appropriate bounds that enable generic code use.

Timer traits as of the 0.2.7 release:

• Docs
• Source

Relevant issues/PRs:

• Quadrature encoder trait #51
• Your issue here!

Please feel free to participate, highlight your current use cases, problems and provide solutions.