Issue #16827: Make Interpreter introduction section of the tutorial more
focussed and move advanced section and customization information to a separate
file called appendix.

Patch credits: Jamayla Wiley, Ya-Ting Huang and James Brewer.
merge from 3.4

Issue #16827: Make Interpreter introduction section of the tutorial more
focussed and move advanced section and customization information to a separate
file called appendix.

Patch credits: Jamayla Wiley, Ya-Ting Huang and James Brewer.