Revert "DateSerializer and LocaleSerializer enhacements and tests"

This reverts commit c43b0552f2921ba131c7e3827ac3b9d77d3d0a03.
DateSerializer and LocaleSerializer enhacements and tests

(*) Enhacements to DateSerializer: use identity comparison
(*) Enhacements to LocaleSerializer:
	- removed copy method, as Locale isImmutable
	- reordered and enhacements to the Locale constants search inside the create method
	- optimized write method: use writeAscii for language and country fields (not for variant)
(*) Added tests for PR #165
Fiexd #170. Add Unit test to ensure fix of #170 contributed by fix#176
Fiexd #170. Add Unit test to ensure fix of #170 contributed by fix#176
Merge origin/enhacements-to-default-serializars into enhacements-to-default-serializars
Fiexd #170. Add Unit test to ensure fix of #170 contributed by fix#176