Create initial unit test for tcplfit2

[brown-jason]

Find an example set of data that is identical to something that would be processed in httr or toxcast and create a test using testthat package so that when we make changes in the future we can ensure the current analyses are not effected

1. Research testthat package
2. Create a test with a known output that tests concrespcore function and ensures repeatable output

[sedavid01]

@brown-jason, we may also want to get an example from Josh Harrill or Derik Haggard for HTPP data.

[sedavid01]

For now, let us start with a simulation example for testing, then we can add in 'example data' from the various potential data streams. See code chunk above "General Shape" figure in the tcpl_v3 Data processing vignette as an example for simulation data if needed. Suggest only using at the very least 5 doses and likely no more than 10 doses for simulated DR data.

[sedavid01]

This branch was merged into 'dev' and is now resolved. Closing this ticket.