Recent Modification to Fallback Trim setting allows for Grace capability instead of strictly Trim

This is now "Fallback"  and allows for both positive and negative numbers.  This is to allow Fallback Grace as well as Fallback Trim

Negative Numbers back up to find the previous increment and Positive Numbers go forward to find the next increment

To use a Strictly Fallback Trim, a user must now apply a Positive value to the Shift Start and a Negative Value to Shift End

To use a Strictly Fallback Grace, a user must apply a Negative value to the Shift Start and a Positive value to Shift End

Users can also implement a hybrid such as Trim Start and Grace End or vice versa.

For All clients that had an existing Fallback Trim rule for Shift End, we inverted their existing number for them so that the expected behavior remains correct.

This change was applied to both HTML and Silverlight, because otherwise the HTML could create an environment that would not only give different results in Silverlight, but would break.