remove deprecated pkg_resources and replace with importlib

Author: larsbuntemeyer

pyremo/__init__.py

@@ -1,4 +1,4 @@
-import pkg_resources
+from importlib.metadata import version as _get_version
 
 from . import codes, data, physics, remo_ds, tutorial
 from .cal import parse_absolute_time, parse_dates
@@ -8,7 +8,7 @@
 from .tables import domains, vc
 
 try:
-    __version__ = pkg_resources.get_distribution("pyremo").version
+    __version__ = _get_version("pyremo")
 except Exception:
     # Local copy or not installed with setuptools.
     # Disable minimum version checks on downstream libraries.