[autofit] Add blue-zone support for Sinhala script. This essentially moves the Sinhala script from the `Indic' hinter to the `Latin' hinter. * src/autofit/afblue.dat: Add blue zone data for Sinhala. * src/autofit/afblue.c, src/autofit/afblue.h: Regenerated. * src/autofit/afscript.h: Add Sinhala standard character and move data out of AF_CONFIG_OPTION_INDIC block. * src/autofit/afranges.c: Move Sinhala data out of AF_CONFIG_OPTION_INDIC block. * src/autofit/afstyles.h: Update Sinhala data; in particular, use AF_WRITING_SYSTEM_LATIN.