Automate the generation of rtfd files at build time

Right now, rtfd files that we use for the Mac installers are manually generated. Any change in these files need to be manually done which poses an issue for the localization team. We have to send the english strings and then manually create rtfd files for localized strings returned from the i18n team.

This change should create rtfd files automatically for each supported i18n language at build time by pulling in information from the Localizable.strings files at build time.