[TASK] Add packageKey attribute to ifHasRole view helper

This change adds support for handling a packageKey to the ifHasRole
view helper. It can be used in three ways:

1) The 'old' way, with just a string like 'Administrator'
   This will result in a check for the Administrator role within
   the current package (fetched from the controllerContext)
2) With a full role identifier like 'Foo.MyPackage:Administrator'
3) Using both, the role attribute and packageKey attribute

This was once Iae92119bf9f8d6125211d1e4b1e42a0a513d804b but had to be
reverted after an accidental merge.

Change-Id: If4c762c5de51c747495a3602eb56c56dd3972c73
Related: #37451
Releases: 2.0, master