v1.6.0-RC2

• Added @XmlRootElement annotation to MzIdentMlType JAXB class to enable proper marshalling.
• Changed how precursor ions are reported. PrecursorInfo now provides mzTarget as the actual targeted m/z, and also mzTargetMono, which is the assumed monoisotopic m/z of that ion.
• Fixed regression bug in mzXML header parsing. Original files without parent location were causing NPEs.
• PepXML parser updated to pepxml schema v120. Includes PTM Prophet and related changes.
• Multiple improvements to mzML parsing.
• Support for ReferenceableParamGroups in mzML.
• Significant non-indexed files parsing speed up.