Merge branch 'f-permission-checks' into 'dev'

...ava/org/caosdb/server/database/access/AbstractAccess.java

src/main/java/org/caosdb/server/query/Backreference.java

src/main/java/org/caosdb/server/query/Query.java

src/main/java/org/caosdb/server/query/SubProperty.java

src/main/java/org/caosdb/server/utils/ResultSetIterator.java

src/test/java/org/caosdb/server/query/QueryTest.java