Diff uses full entity

[rwedge]

Pull Request Description

Fixes how the Diff primitive is calculated so that it will use all available data when calculating diff. This should make returned values more predictable.

---

After creating the pull request: in order to pass the changelog_updated check you will need to update the "Future Release" section of docs/source/changelog.rst to include this pull request.

[kmax12]

LGTM

[codecov-io]

Codecov Report

Merging #824 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #824      +/-   ##
==========================================
+ Coverage   98.12%   98.12%   +<.01%     
==========================================
  Files         119      119              
  Lines       10882    10897      +15     
==========================================
+ Hits        10678    10693      +15     
  Misses        204      204

Impacted Files	Coverage Δ
...retools/primitives/standard/transform_primitive.py	100% <100%> (ø)	⬆️
...s/tests/primitive_tests/test_transform_features.py	98.48% <100%> (+0.04%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 9fce745...89cb1c4. Read the comment docs.