Author: Mark Nelson
MDL-52035 auth_lti: added auth plugin
http://git.moodle.org/gw?p=moodle.git;a=commit;h=1d8886fa31648d65f6e59879400e7242ade606e0
http://github.com/moodle/moodle/commit/1d8886fa31648d65f6e59879400e7242ade606e0
+ 3.1 en [auth_ltidescription,auth_lti]
+ 3.1 en [pluginname,auth_lti]