Code cleanup


ImportLDIFReader.java:
In readEntry() now return EntryInformation and no longer accept it as a parameter.
Moved EntryInformation here from Importer. It fits better here after changing readEntry().
EntryContainer:
All fields are now final + added a constructor.
Used AutoRefactor

Importer.java:
Moved EntryInformation to where it logically begins: ImportLDIFReader
Renamed getSuffix() and generateIndexID() to prepareSuffix() and generateIndexIDs().
In mustRebuild(), removed one parameter which value can be obtained via a field.
ImportTask and AppendReplaceTask:
- removed EntryInformation fields
- in call0(), consequence of the change to ImportLDIFReader.readEntry() + rewrote the code a bit to make it even shorter