doc/conf.py: Clear sys.path before importing Roundup __version__

             This ensures that 'unkown version' is inserted when
            `roundup` is importable from other location in sys.path

Author: techtonik

doc/conf.py

@@ -13,12 +13,21 @@
 
 import sys, os
 
+
+# Read Roundup version by importing it from parent directory,
+# this ensures that 'unkown version' is inserted even if
+# `roundup` is importable from other location in sys.path
+SYSSAVE = sys.path
+DOCROOT = os.path.abspath(os.path.dirname(__file__))
+sys.path = [os.path.dirname(DOCROOT)]
 try:
-    sys.path.insert(0, os.pardir)
-    from roundup import __version__ as roundupversion
-    sys.path.pop(0)
+    from roundup import __version__ as VERSION
+    SHORTVER = '.'.join(VERSION.split('.', 2)[:2])
 except ImportError:
-    roundupversion = '(unknown version)'
+    VERSION = SHORTVER = '(unknown version)'
+finally:
+    sys.path = SYSSAVE
+
 
 # If your extensions are in another directory, add it here. If the directory
 # is relative to the documentation root, use os.path.abspath to make it
@@ -53,9 +62,9 @@
 # built documents.
 #
 # The short X.Y version.
-version = '.'.join(roundupversion.split('.', 2)[:2])
+version = SHORTVER
 # The full version, including alpha/beta/rc tags.
-release = roundupversion
+release = VERSION
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.