raphaelquast/EOmaps: EOmaps v4.2.1

A bugfix release that greatly reduces import time!

• 🕐 greatly reduced "plain" import-time
  • "heavy" modules such as 'datashader', 'xarray' etc. are now lazily imported only when needed
  • this reduces runtime of from eomaps import Maps in a fresh terminal from ~5sec to ~1sec
• 🍃 m.add_marker(...) now supports the "layer" kwarg
• 🍃 m.show() now automatically calls plt.show() to actually draw the figure if matplotlib is in non-interactive mode

• legends for WebMap services are now updated based on the visible layer
• m.add_marker now only draws newly added markers (instead of updating all dynamic artists)
• avoid using pkg_resources to identify package-version (use explicit _version.py instead)