Added version management a la PyHEADTAIL

Author: aoeftiger

__init__.py

@@ -0,0 +1 @@
+from _version import __version__

_version.py

@@ -0,0 +1,16 @@
+import os, subprocess
+worktree = os.path.dirname(os.path.abspath(__file__))
+gitdir = worktree + '/.git/'
+try:
+    __version__ = subprocess.check_output(
+        'git --git-dir=' + gitdir + ' --work-tree=' +
+        worktree + ' describe --long --dirty --abbrev=10 --tags', shell=True)
+    __version__ = __version__.rstrip() # remove trailing \n
+    __version__ = __version__[1:] # remove leading v
+    # remove commit hash to conform to PEP440:
+    split_ = __version__.split('-')
+    __version__ = split_[0]
+    if split_[1] != '0':
+        __version__ += '.' + split_[1]
+except:
+    __version__ = '(no git available to determine version)'