Feature: Support for multiple email addresses synced from LDAP

[stertingen]

• Gitea version (or commit ref): 1.12.2 built with GNU Make 4.2.1, go1.14.4 : bindata, sqlite, sqlite_unlock_notify
• Git version: 2.24.3
• Operating system: official docker container
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  • MySQL
  • MSSQL
  • SQLite
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Description

We have a central LDAP server for our users who may have multiple email addresses, which are also stored on the LDAP server. I'd like to propose that the LDAP authentication source shall look for multiple email addresses of that user and add these to the user profile.

Each user should be able to add and remove more addresses on their own, but addresses synced from the LDAP server should only be removable by removing them from the LDAP server.