MDL-41476 scorm_12.js - increasing size of CMIString if scorm12compatable is false

Increasing the size of CMIString256 to 4096 and CMIString4096 to 16384 if the scorm12compatable
is set to false in the scorm admin settings. When scorm12compatable is set to true the size of
CMIString256 is 256 and CMIString4096 is 4096.