use 'maint' for maintenance branch version_extra

IPython/core/release.py

@@ -22,7 +22,7 b" name = 'ipython'"
 _version_major = 2
 _version_minor = 1
 _version_patch = 0
-_version_extra = 'dev'
+_version_extra = 'maint'
 # _version_extra = 'rc1'
 # _version_extra = ''  # Uncomment this for full releases
 

IPython/html/static/base/js/namespace.js

@@ -7,7 +7,7 b''
 
 var IPython = IPython || {};
 
-IPython.version = "2.1.0-dev";
+IPython.version = "2.1.0-maint";
 
 IPython.namespace = function (ns_string) {
     "use strict";