Dynamically load oauth-related libraries

[MarcialRosales]

Proposed Changes

It addresses one issue raised and two more issues found but not raised:

• Load oauth javascript dependencies only when they are required #11421
• the logged in user's name should only be a hyperlink to the user's record when the user is an administrator and it has been authenticated with the internal backend. In other words, if the user was authenticated with oauth or ldap or http, there is no internal record of the user hence the username should not be rendered as a hyperlink.
• disable browser login dialog-box and instead always redirect the user to the login html page when either the credentials are wrong or user is not authorized or session has expired

Types of Changes

What types of changes does your code introduce to this project?
Put an x in the boxes that apply

• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)
• Build system and/or CI

[michaelklishin]

The forced push was a rebase.