Sidebar: rename media-globe/ to media_globe/ (#1973)

So that it can be an importable package.
This is in preparation for setuptools packaging.

plugins/Sidebar/SidebarPlugin.py

@@ -49,7 +49,7 @@ class UiRequestPlugin(object):
                     yield part
         elif path.startswith("/uimedia/globe/"):  # Serve WebGL globe files
             file_name = re.match(".*/(.*)", path).group(1)
-            plugin_media_file = "%s-globe/%s" % (media_dir, file_name)
+            plugin_media_file = "%s_globe/%s" % (media_dir, file_name)
             if config.debug and path.endswith("all.js"):
                 # If debugging merge *.css to all.css and *.js to all.js
                 from Debug import DebugMedia