use IVall_cols for parallel circuits in substring that are not the same
use IVall_cols for parallel circuits in substring that are not the same

* use IVprev_cols to combine parallel circuits that are the same
* keep I and V together in IVcols
* check if cell position pattern for adjacent columns are identical, if not, then combine parallel circuits and reset prev_col
* otherwise append the prev_col and continue
* combine parallel circuits by looping over IVprev_cols, then combining resulting series circuit, store results in IVall_cols
* if IVall_cols is only 1 tuple, then that's the substring, otherwise, combine them in parallel

SunPower/PVMismatch