Move version number from __init__.py to __main__.py

This will allow the access from outside the package. setup.py and the
Makefile can use this version number. The __init__.py script imports
the version number, so the module will have the __version__ variable
as usual.

setup.py

@@ -6,9 +6,11 @@ __license__ = "GPLv3"
 
 from setuptools import find_namespace_packages, setup
 
+from src.revpicommander.__main__ import __version__
+
 setup(
     name="revpicommander",
-    version="0.9.10rc3",
+    version=__version__,
 
     packages=find_namespace_packages("src"),
     package_dir={'': 'src'},