Add galgebra.__version__ for easy version inspection (#172)

This uses the same approach as clifford and pyganja

Author: eric-wieser

galgebra/__init__.py

@@ -22,3 +22,4 @@
 
 from __future__ import absolute_import, division
 from __future__ import print_function
+from ._version import __version__

galgebra/_version.py

@@ -0,0 +1,8 @@
+# Package versioning solution originally found here:
+# http://stackoverflow.com/q/458550
+
+# Store the version here so:
+# 1) we don't load dependencies by storing it in __init__.py
+# 2) we can import it in setup.py for the same reason
+# 3) we can import it into your module
+__version__ = '0.4.4'

setup.py

@@ -1,14 +1,17 @@
 #!/usr/bin/env python
 from setuptools import setup, find_packages
 from distutils.core import Extension
+import os
+
+version_path = os.path.join('galgebra', '_version.py')
+exec(open(version_path).read())
 
-VERSION = '0.4.4'
 LONG_DESCRIPTION = """
 Symbolic Geometric Algebra/Calculus package for SymPy. BSD License.
 """
 
 setup(name='galgebra',
-      version=VERSION,
+      version=__version__,
       description='Symbolic Geometric Algebra/Calculus package for SymPy.',
       author='Alan Bromborsky',
       author_email='[email protected]',