Add learner's grade to the certificate

[gaurav1984]

Requested in 654674-zen

Add the ability to show Lerner's grade in the Final Certificate, plus the relevant placeholder text.

[Adminifhta]

This will be very helpful in being able to acknowledge good performance such as "Passed with Distinction/Merit; etc..."

I hope this plugin will be addressed more frequently in development as it has very good application.

[richardmtl]

Again in 2691105-zen

[aicee]

https://wordpress.org/support/topic/show-score-obtained-by-the-student/

[aicee]

5704148-zen