Add cloud common protos directory (#1517)
Add cloud common protos directory (#1517)

* Add CommonProtos directory

* Add tests for CommonProtos

* Remove "Cloud" from src directory, update composer.json

* Exclude style check on CommonProtos

* Fix autoload config

* Update to fix doc generation

* Address PR comments

* Add note to CommonProtos README

* Bump gax and common proto versions

* Update debugger composer file

* Fix Debugger gax dependency

* Add common protos to manifest

googleapis/google-cloud-php-core