Applied patch from Mohamed Gaber that fixes the issue of the

configuration script not doing tilde expansion on paths in the
configure command line.  This patch uses python3 and is cross-
platform (existing code used "readlink -f" and so also had
problems on Mac OSX).  Also changed the configuration script
so that the value for --enable-sky130-pdk can have the
libraries/ directory on the end or not, and it will find the
path regardless.