Fixed isPrivate() of file

Conflicts:
	src/main/java/net/sourceforge/fenixedu/domain/File.java
Removed override of getPermittedGroup of extensions of File: ResearchResultDocumentFile. It was harming the group translation

Conflicts:
	src/main/java/net/sourceforge/fenixedu/applicationTier/Servico/research/result/CreateResultDocumentFile.java
	src/main/java/net/sourceforge/fenixedu/applicationTier/Servico/thesis/CreateThesisDissertationFile.java
	src/main/java/net/sourceforge/fenixedu/domain/research/result/ResearchResult.java