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Cannot perform a 'Save Data from PLC to File' if bits are force on.

Goals and Symptoms
If there are forced bits in the PLC, Unity will not allow the user to perform a 'Save Data from PLC to File'.  Prior to Unity 12, this
feature was allowed.

Facts and Change

Causes and Fixes​
Prior to Unity 12, the user was allowed to save the PLC data to a file even when there was a forced bit in the PLC.
Upon restoring the data to the PLC the forced bit state condition would also get restored. The forced bits did not show
up in the status bar and there was no way to determine the address of the forced bits.   

if the user was not aware that there were any forced bits in the data being restored to the PLC,  it would result in an
unwanted condition of the connected field equimpment.  Even if the user was aware that there were forced bits saved 
in the data file,  this could also result in an unwanted conditon of the connected field equipment because there was
no way for determining what the forced bits were.  

This was considered to be a bad behavior in Unity and the ability to save the PLC data to a file when there was a foced
bit in the PLC was removed.
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