added GNRXC function for multiple widths
Prep for GNRXC integration with TDWLARI
GNRXC module integrated into TDWLARI
[FIX] WLATDRI now properly accounts for width fraction and aspect ratio
WLATDRI with GNR updtes
GNR pitch calculation sped up significantly

Use sanity check + binary search to more rapidly find best GNR pitch
Revert GNR capacitance to actual venkatesan calculation
[FIX] GNRs allowed to have different spacing (prev assumed half-pitch spacing)
[FIX] function timing works properly
reverting params for GNRs
Sandbox models for size-dependent copper resistivity
Added Cu resistivity functions to XCM
[CLEAN] removed empty file
<XCM> Added Cu wire param calculations
<XCM> Added routines to find best Cu wire dimensions
<XCM> Updated WLATDRI to use new Cu/GNR routines
<VIP> Added plot for unrepeatered vs repeatered pitch
[WIP] KNOWN ISSUES Partial update of GNRXC routine

Updating GNR routine to mirror Cu calculation
Current issue: Doubling min pitch for feature-size limited metal layers
<XCM>[FIX] incorrect usage of min_pitch instead of wire width in gnrxc routine
<XCM> Cu and GNR wire param functions now check min pitch first

This ensures we use the lowest pitch we can actually get away with, and
ensures that checks based on the min pitch later on will function
correctly. Previously, since the new CU/CUREP/GNR wire param functions
used a binary search bounded at the min pitch, but never actually
checked the min pitch, wires could never actually be assigned the
minimum pitch, just arbitrarily close to it (depending on the number of
binary search generations allowed).