Added IS_INSTALLED check and SCCM Status MIFs

Added checks to see if the product is currently installed on the target
system, and take the following actions.
If InstallState is 1 and ProductCode is found on the system --> Write a
Log message and Exit
If InstallState is 0 and ProductCode is found on the system  --> Fix
UMHS Branding by resetting InstallState to 1
If InstallState is 1 but ProductCode is NOT found on the system -->
Install Product
If InstallState is 0 and ProductCode is NOT found on the system  -->
Install Product

Also inserted SCCM-CreateStatusMIF action lines to appropriate
milestones in the installation flow.