* Add descriptors test

* Update descriptors tests

* Add public descriptors

* Add test_desriptors.proto to test script

* Update composer files

* Remove references to GPBType, update tests to be compatible with c

* Update for c extension compatibility

* Remove nested enums for descriptor, update tests

* Strip leading '.' from descriptor name

* Update tests with test for getClass, fix OneofDescriptor

* Add new files to Makefile.am

* Follows proper autoloading standards
 - Splits PHP classes in descriptor.php into separate files
 - Splits MapFieldIter and RepeatedFieldIter into separate files
 - Moves descriptor.php to Internal/functions.php
 - Moves all namespaced functions into Iternal/functions.php

* fixes Makefile.am for added php files

* [PHP] moves all functions to GPBUtil

* removes description.php from the makefile

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