Adding a cr-rc fiting fucntion

Overview

Adding a new fitting function and fitting strategy that comes from solving a cr-rc circuit. This provides a closer match to the true shape of some pulses by modeling the overshoot and baseline shift.

Tested

Running the lolx_cr_rc.json gives similar results and can extract the overshoot

./bin/EventViewer experiments/LOLX_cr_rc.json 0 -1 5