Fix commits by version (remove --all for git log)

gitchart.py

@@ -298,7 +298,7 @@ class GitChart(object):
             #   v0.3.0         =>  0.3.0
             tag2 = re.sub('([^0-9]+)', ' ', tag).strip().replace(' ', '.')
             commits[tag2] = len(
-                self._git_command(['git', 'log', '--all',
+                self._git_command(['git', 'log',
                                    oldtag + '..' + tag if oldtag else tag,
                                    '--pretty=oneline']))
             oldtag = tag