Author: Damyon Wiese
MDL-58280 fileconverter_googledrive: More helpful errors
Detect some config errors and give a better error message.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=0b1a14aef925a506c4db59bbe579a4b3459ab149
http://github.com/moodle/moodle/commit/0b1a14aef925a506c4db59bbe579a4b3459ab149
+ 3.3 en [test_issuerinvalid,fileconverter_googledrive]
+ 3.3 en [test_issuernotenabled,fileconverter_googledrive]
+ 3.3 en [test_issuernotconnected,fileconverter_googledrive]
+ 3.3 en [test_issuernotset,fileconverter_googledrive]