Add support for creating dialogs, and add an About dialog.

This adds bootstrap-dialog to help with creation of nice dialogs,
and adds the ability for modules to render Javascript into the
browser, and specify onclick handlers in the menu system.

Also add a basic About dialog, using the new infrastructure and
showing some useful info about the application.

web/config.py

@@ -28,6 +28,9 @@ APP_REVISION = 0
 # for GA releases.
 APP_SUFFIX = 'dev'
 
+# Copyright string for display in the app
+APP_COPYRIGHT = 'Copyright 2014 - 2015, The pgAdmin Development Team'
+
 # DO NOT CHANGE!
 # The application version string, constructed from the components
 APP_VERSION = '%s.%s.%s-%s' % (APP_MAJOR, APP_MINOR, APP_REVISION, APP_SUFFIX)