For open edX sites, provide info on adding registration keys

Description

Follow on to / OSPR-933.

See edx-code discussion here:
https://groups.google.com/forum/#!msg/edx-code/y5I80Pp8TEk/X1NdnhkgJwAJ
with info from

There are two keys that currently need to be added (not just set) in the lms.env.json file in order to add custom fields to the registration form.

install_operations/source/configuration/customize_registration_page.rst:

Steps to Reproduce

None

Current Behavior

None

Expected Behavior

None

Reason for Variance

None

Release Notes

None

User Impact Summary

None

Status

Assignee

Unassigned

Reporter

Alison Hodges

Labels

Reach

None

Impact

None

Platform Area

None

Customer

None

Partner Manager

None

URL

None

Contributor Name

None

Groups with Read-Only Access

None

Actual Points

None

Category of Work

None

Platform Map Area (Levels 1 & 2)

None

Platform Map Area (Levels 3 & 4)

None

Story Points

1

Epic Link

Due date

2016/01/06

Priority

CAT-3
Configure