Move to java11.

build.gradle

solve/build.gradle

solve/src/main/jastadd/ApplyChanges.jadd

solve/src/main/java/SocialNetwork/SocialNetworkPackage.java

...ain/java/SocialNetwork/impl/SocialNetworkFactoryImpl.java

...ain/java/SocialNetwork/impl/SocialNetworkPackageImpl.java

...c/main/java/SocialNetwork/impl/SocialNetworkRootImpl.java

solve/src/main/java/SocialNetwork/impl/SubmissionImpl.java

solve/src/main/java/SocialNetwork/impl/UserImpl.java

...a/de/tudresden/inf/st/ttc18live/LiveContestDriverEMF.java

...a/de/tudresden/inf/st/ttc18live/LiveContestDriverXml.java

solve/src/main/java/de/tudresden/inf/st/ttc18live/Main.java

...a/de/tudresden/inf/st/ttc18live/parser/ParsedComment.java

...tudresden/inf/st/ttc18live/parser/ParsedModelElement.java

...java/de/tudresden/inf/st/ttc18live/parser/ParsedPost.java

...udresden/inf/st/ttc18live/parser/ParsedSocialNetwork.java

...e/tudresden/inf/st/ttc18live/parser/ParsedSubmission.java

...java/de/tudresden/inf/st/ttc18live/parser/ParsedUser.java

...f/st/ttc18live/parser/change/ParsedAssociationChange.java

...e/parser/change/ParsedAssociationCollectionInsertion.java