convert remnants of String to OUString in filter module
convert remnants of String to OUString in filter module

Change-Id: I83cea804b73d9219019354223bd2c966f52c5688

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core