Draft: Reboot of ogsdatacopare
This MR restarts the development of ogsdatacompare.
This replaces code in EXPERIMENTAL/ogsdatacompare and will remove it at some point. Also !15 (closed) will be closed in favor of this one.
It is written from scratch, no or very little code will be reused from the original code, as it was build on top of Matplotlib and this MR is based on meshlib and meshplotlib.