Add BirthdayType and AnniversaryType enum values
Rename DetailTypes -> DetailType
Rename SortByField to DisplayLabelOrder

The value really sets the order of the display label text, so the
current name is misleading. The value does affect the sort order,
but only because the model currently defaults to sorting by display
label.
Merge pull request #60 from blammit/enum-changes

Enum changes