Add Childcare Cost Simulation (CAP data)

[jwal1024]

Build on the first simple simulation to take into account the actual costs of minimum standard and high quality childcare using childcare cost data stratified by child age.

[MaxGhenis]

Nice, just checking this is only intended to be the data? If you're looking to add analysis code to this PR, please convert it to a draft (upper right of GitHub UI).

Could you also move the file to the jb/data folder and add a README.md there linking the source?

[pep8speaks]

Hello @jwal1024! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file jb/child_allowance.py:

Line 14:80: E501 line too long (97 > 79 characters)

• In the file jb/child_allowance_costs.py:

Line 16:80: E501 line too long (97 > 79 characters)
Line 56:80: E501 line too long (85 > 79 characters)
Line 107:80: E501 line too long (100 > 79 characters)
Line 109:80: E501 line too long (80 > 79 characters)
Line 111:26: W292 no newline at end of file
Line 111:26: W292 no newline at end of file
Line 111:26: W292 no newline at end of file