pdTextBox: prevent "Beep" on Enter key press

Also, make .Text the default property, so I can drop this in over
existing text box code.
Command Bar: add preset support for pdTextBox

As long as pdTextBox names remain the same as the text boxes they
replace, all existing preset data will work just fine!
New Layer dialog: convert layer name text box to pdTextBox

This completes the last item for user-entered layer names to fully
support Unicode.