Doc review 8 26 2

@tthompson-okta @croche-okta @stsai-okta @srinivasanagandla-okta @lboyette-okta @wdawson-okta @hoanguyen-okta @karlmcguinness-okta @cwu-okta 

Mostly for Trevor--reset factors API doc.
Just a nit, but I would change the second sentence to say "All MFA factor enrollments are returned to the unenrolled state". Also I would add "This link is only present if the user is currently enrolled in one or more MFA factors".