add Employer side payroll parameters

[bodiyang]

This PR address the employer side payroll tax offset issue. This PR will split the payroll tax parameters, FICA_mc_trt and FICA_ss_trt, into four parameters on the employer side and employee side, as FICA_mc_trt_employer, FICA_mc_trt_employee and FICA_ss_trt_employer, FICA_ss_trt_employee

[codecov]

Codecov Report

Merging #2669 (3cf3a21) into master (086d302) will decrease coverage by 0.01%.
The diff coverage is n/a.

❗ Current head 3cf3a21 differs from pull request most recent head 8255631. Consider uploading reports for the commit 8255631 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2669      +/-   ##
==========================================
- Coverage   98.54%   98.52%   -0.02%     
==========================================
  Files          14       14              
  Lines        2609     2585      -24     
==========================================
- Hits         2571     2547      -24     
  Misses         38       38              

Flag	Coverage Δ
unittests	98.52% <ø> (-0.02%)	⬇️

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

Impacted Files	Coverage Δ
taxcalc/data.py	99.23% <0.00%> (-0.02%)	⬇️
taxcalc/policy.py	100.00% <0.00%> (ø)
taxcalc/records.py	100.00% <0.00%> (ø)
taxcalc/growdiff.py	100.00% <0.00%> (ø)
taxcalc/taxcalcio.py	100.00% <0.00%> (ø)
taxcalc/calculator.py	100.00% <0.00%> (ø)
taxcalc/parameters.py	100.00% <0.00%> (ø)
taxcalc/consumption.py	100.00% <0.00%> (ø)
taxcalc/growfactors.py	100.00% <0.00%> (ø)

[jdebacker]

@bodiyang This PR is looking good. I think the one CI failure is pointing towards at least one other place to update the parameter. See FAILED taxcalc/tests/test_policy.py::test_json_reform_url.

[bodiyang]

@bodiyang This PR is looking good. I think the one CI failure is pointing towards at least one other place to update the parameter. See FAILED taxcalc/tests/test_policy.py::test_json_reform_url.

This failure should be solved after the PR get merged, I think we don't need to make change here ~ because it is a comparison between the values read from the url of ptaxes0.json file and the values in the test file.

As I have made the change in ptaxes0.json, this test failure will be solved as the PR get merged and the url get updated to the new values.

[jdebacker]

this failure should be solved after the PR get merged

@bodiyang -- you are correct.

Let me review one more time and let this sit for a day before merging. But it's looking good to me. Thanks.

[jdebacker]

Thanks for this PR @bodiyang. This will break backwards compatibility, so I think we'll want to merge this into the V4 branch.

[jdebacker]

@bodiyang, I've just updated the v4_development branch to incorporate the latest changes on the master branch. Would you mind editing this PR to direct your changes to the v4_development branch rather than master?

[bodiyang]

@bodiyang, I've just updated the v4_development branch to incorporate the latest changes on the master branch. Would you mind editing this PR to direct your changes to the v4_development branch rather than master?

Have redirected to v4_development branch

[jdebacker]

@bodiyang I've merged your PR into the v4_development branch. I understand this the first part of a series of changes, so I just wanted to note that you will make those changes working off of the v4_development branch.