Provide the ability to override the default caret color of the MaskedInput control

An exception is thrown in iOS when attempting to paste something that will result in the text being longer than the mask.

Available in the R3 2018 SP release.

We can consider exposing TextAlignment property that should also affect the Watermark.

When the mask is set to be Regex and in code the InputValue of the control is set, the validation is not triggered and the error message is visualized.

When in a TableView's ViewCell, the user has to use a touch and hold gesture on the control in order for the control to gain focus. Additionally, once the touch is released, the focus is lost.

<TableView>
   <ViewCell>
        <RadMaskedInput>

Currently when regex is used and the InputValue is bound and the control is focused several placeholders are added. This is incorrect behavior. The placeholders should not be added at all in regex scenarios.

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Workaround: Set Placeholder property to "" (empty string)

MaskedInput: [iOS] Transparent BorderStyle is not applied correctly.

As a workaround, the InputValue could be set at a later stage according to the concrete scenario.