JS: override 'getDefaultString' for UnitTypeInput
JS: override 'getDefaultString' for UnitTypeInput

Shows the default unit correctly in the Input Editor.

Signed-off-by: Harry King <409587b9e6671aa0763646191d292852dc49a658@gmail.com>

jaamsim/jaamsim,jaamsim/jaamsim,jaamsim/jaamsim,jaamsim/jaamsim