* [PHP] Remove PHP related rules from root gitignore
After conversation with @ackintosh we've agreed that every PHP codegen
should create it's own `.gitignore`. Client libraries(SDKs) should ignore
`composer.lock` file while server stubs better do opposite.
* [PHP] Set .gitignore as default supporting file
* [PHP] Add default gitignore to Client SDK
* [PHP] Add default gitignore to Laravel
* [PHP] Add default gitignore to Lumen
* [PHP] Add default gitignore to Silex
Seems like issue #663 and pull request #681 missed this security script,
I've changed output path in bin/security/silex-petstore-server.sh.
* [PHP] Update Slim
* [PHP] Add default gitignore to Symfony
I've copied few old rules from root gitignore to local one. These rules
should be reviewed by original SymfonyCodegen authors.
* [PHP] Add default gitignore to Zend
* [PHP] Refresh Openapi3 client samples
* [PHP] Add refs to .gitignore templates collection
