implementation for delete
removed comment
added implementations for missing DAOs
added implementations for missing DAOs
changed unchecked loading from database. now via loadAll(X.class)-method:x
renamed to VariableDefinition
increased version
added comments for class
merged

Merge branch 'master' of 10.6.9.195:missy/disco-persistence-relational

Conflicts:
	pom.xml
added DAO for PeriodOfTime
implemented getAll() in an abstract way, valid for all subclasses
removed redundant code for getAll-method
overrides getByExample from inherited class
refactored old disco model type
added implementation for NoteDAO
fixed null return
new parent version
extracted to gesis-ddi-persistence module
new parent version
refactoring package names