Add img registration

[DannieSheng]

Describe your changes
Add img_registration function that is capable of collecting (interactive framework) user-clicked points on reference and target image and align two images

Type of update
Is this a:

• New feature or feature enhancement
• Update to documentation
• Work in progress

Associated issues
#715

[codecov]

Codecov Report

Merging #729 (842a90a) into 4.x (bf4e52b) will decrease coverage by 0.62%.
The diff coverage is 49.39%.

❗ Current head 842a90a differs from pull request most recent head 5a93d0d. Consider uploading reports for the commit 5a93d0d to get more accurate results

@@             Coverage Diff             @@
##               4.x     #729      +/-   ##
===========================================
- Coverage   100.00%   99.37%   -0.63%     
===========================================
  Files          159      159              
  Lines         6725     6756      +31     
===========================================
- Hits          6725     6714      -11     
- Misses           0       42      +42     

Flag	Coverage Δ
unittests	99.37% <49.39%> (-0.63%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
plantcv/plantcv/annotate/img_registration.py	23.63% <23.63%> (ø)
plantcv/plantcv/annotate/__init__.py	100.00% <100.00%> (ø)
plantcv/plantcv/transform/warp.py	100.00% <100.00%> (ø)
plantcv/plantcv/crop.py	100.00% <0.00%> (ø)
plantcv/learn/naive_bayes.py	100.00% <0.00%> (ø)
plantcv/plantcv/plot_image.py	100.00% <0.00%> (ø)
plantcv/plantcv/roi/roi2mask.py	100.00% <0.00%> (ø)
plantcv/plantcv/roi/roi_methods.py	100.00% <0.00%> (ø)
plantcv/plantcv/morphology/prune.py	100.00% <0.00%> (ø)
plantcv/plantcv/morphology/find_tips.py	100.00% <0.00%> (ø)
... and 15 more

[nfahlgren]

Refactor to utilize the new annotate subpackage

Accidentally approved, meant to request changes

[nfahlgren]

Refactor to utilize the new annotate subpackages

[HaleySchuhl]

Archiving for now