CC3D data -> MAT file; S_new = 0.01*S_orig

Imported Garrett's data from CompuCell3D into MATLAB, then saved as
StemCell_v_mcs.mat
- 20 trials of stem cell population data (p0=1, h=0, d=0)
- Have not yet fitted a curve to data yet

Realized that the stem-cell-fraction data inputed to the Tumor Data.mat
files was too large by a factor of 100
- Forgot to account for the fact that the data given is a percent ->
need to divide by 100 to get the decimal value
- variables changed: 4 s_[cell line]_[radiation dosage] variables, 2
csc_pop_[cell line]_[radiation dosage] variables
- also created a new fit for v using correct s-values (result = original
result * 100)

Fixed a few bugs in euler2.m
- p = p0/(1+h*(1-s(i))) not p0/(2*(1+h*(1-s(i))))
- added comments to euler2.m, eqn0.m, and eqn1.m
- Note: euler2.m solves a system of ODE's in eqn0 and eqn1 (in this
case, for S and X).
- Note: euler.m was specifically written for a 2-species system with
feedback with parameters q, s. The ODE functions are not in separate
files

Added regulatory term to costFunction (although it may not be necessary)