Merge pull request #3027 from nickvergessen/ticket/13137
[ticket/13137] Remove schema.json from repository
* nickvergessen/ticket/13137:
[ticket/13137] Create schema.json in build script
[ticket/13137] Improve output of create_schema_files.php
[ticket/13137] Add schema.json file to .gitignore
[ticket/13137] Generate the schema when the schema.json file is not available
[ticket/13137] Remove schema.json file