Use pkg_resources to get the version in docs

Author: muupan

docs/conf.py

@@ -18,9 +18,12 @@
 # documentation root, use os.path.abspath to make it absolute, like shown here.
 #
 import os
+import pkg_resources
 import sys
 sys.path.insert(0, os.path.abspath('..'))
 
+__version__ = pkg_resources.get_distribution('chainerrl').version
+
 
 # -- General configuration ------------------------------------------------
 
@@ -62,9 +65,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '0.0'
+version = __version__
 # The full version, including alpha/beta/rc tags.
-release = '0.1.0'
+release = __version__
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.