* Make reserve names map persistent

* Add DescriptorInternal to map

* Use get_msgdef_desc in encode_decode.c

* Add persistent map for ce=>def and enum=>def

* Replace get_ce_obj

* Remove get_proto_obj

* Remove obsolete fields from Descriptor and EnumDescriptor

* Add cache for descriptor php values

* Add cache for descriptors

* Fix bug

* Avoid add generated file again if it has been added

* Fix the bug upb depends on null-ended str for look up.

* Initialize generated pool impl

* Turn down old generated pool

* Add init entry flag protobuf.keep_descriptor_pool_after_request

By default, it's off. Add protobuf.keep_descriptor_pool_after_request=1 to php.ini to enable it

* Fix zts build