Magnifer Sample Adjustments

[Cameron-Micka]

Overview

A few updates to the Magnifier sample scene:

Plus, a custom inspector for the Magnifier Manager:

Verification

As a reviewer, it is possible to check out this change locally by using the following
commands (substituting {PR_ID} with the ID of this pull request):

git fetch origin pull/{PR_ID}/head:name_of_local_branch

git checkout name_of_local_branch