Default user permissions should be at Reader role

[amurphy-cl]

Currently user role permissions default to Creator role at login. This should be changed so that the default role is Reader for any new user who logs into UpGrade.

If this is reasonably trivial change, let's make it a hotfix for the 5.1 release.

[ppratikcr7]

@danoswaltCL Can we close this?