Added missing plugin templates to manifest

[jpaniagualaconich]

Description

Plugins come with their own templates dir which has to be included in MANIFEST.in

Motivation and Context

Fixes #583

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov]

Codecov Report

Merging #584 (feac861) into master (74221c0) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #584   +/-   ##
=======================================
  Coverage   95.58%   95.58%           
=======================================
  Files          74       74           
  Lines        3194     3194           
  Branches      359      359           
=======================================
  Hits         3053     3053           
  Misses        112      112           
  Partials       29       29           

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[claudep]

Thanks! If you add Fixed #583 or Fixes #583 somewhere in the commit message, the related issue will be automatically closed when this is merged.

[jpaniagualaconich]

@claudep ok, added.

[claudep]

👍