Rdf parser cuts uri prefixes for File.Name, Checksum.Algo, doc.DataLicence

Signed-off-by: Vlad Velici <vlad.velici@gmail.com>
fileType error message gives the incorrect value.

Signed-off-by: Vlad Velici <vlad.velici@gmail.com>
cli tool format action done, close #16

rdf writer: WriteRdf() now handles input and output format strings correctly

Signed-off-by: Vlad Velici <vlad.velici@gmail.com>