Fixes issue #637 bad serialization of default enum values.
Fixes issue #637 bad serialization of default enum values.

TanayParikh/foam2,jacksonic/vjlofvhjfgm,jacksonic/vjlofvhjfgm,TanayParikh/foam2,foam-framework/foam2,foam-framework/foam2,jacksonic/vjlofvhjfgm,foam-framework/foam2,TanayParikh/foam2,foam-framework/foam2,TanayParikh/foam2,foam-framework/foam2