- set `ALLOW_PLANTUML_INCLUDE` only once and decentralized inside the `DiagramResponse` class and call this init method after initializing the server
- set `PLANTUML_SECURITY_PROFILE` to `INTERNET` by default (BREAKING CHANGES)
- add possibility to set PlantUML system properties over a file with `PLANTUML_PROPERTY_FILE`
- adjust documentation
- add "Breaking changes" hint to README