Create repository crd for each Restic repository

[hossainemruz]

Fixes #396
Fixes #392

Code:

• Create repository crd for each restic repository

Test:

• Add test for repository crd

Doc:

• Add doc for repository

[codecov-io]

Codecov Report

Merging #394 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #394   +/-   ##
=======================================
  Coverage   84.61%   84.61%           
=======================================
  Files           1        1           
  Lines          13       13           
=======================================
  Hits           11       11           
  Misses          1        1           
  Partials        1        1

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[tamalsaha]

Fixes #396

@galexrt , this implements Repository CRD and moves the Status section of Restic CRD to Repository.

[tamalsaha]

@emruz-hossain ,

• The event should be written against the Repository object.
• Use CreateOrPatch for Repository https://github.com/appscode/stash/blob/repository/client/clientset/versioned/typed/stash/v1alpha1/util/repository.go
• Add test to ensure that recovered volume can be used in workload without significant change in yaml