Major changes to validateAdditionalFields() and submitForms() functions and added the initiateSchoolContentFunctionality() function

Added the option of running multistep.validateAdditionalFields() and
multistep.submitForms() for a specific school instead of always in
aggregate.  Added the multistep.initiateSchoolContentFunctionality()
function so it can be used as a callback for
multistep.getSchoolContent() Modified the text displayed in the
'school-confirm-btn' in form-multistep.php