Author: John Okely
MDL-53988 mod_lti: Improve error handling and user interface
Only show one, more helpful error instead of two non-helpful errors.
Don't show the 'no configured tools' message if there is a proxy there.
Return to the Tool configure page when editing a proxy if you came
from it.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=0450f5e0819fab1539d58bdabb7c9450917fe176
http://github.com/moodle/moodle/commit/0450f5e0819fab1539d58bdabb7c9450917fe176
+ 3.1 en [failedtocreatetooltype,mod_lti]