Improvements: lazy autoload, jet reclustering, fastobjects and others

- make AutoHandle lazy (speed improvement for unused handles)
- remove usage of GenParticle physics object in GeneratorAnalyzer
(speed improvement)
- introducing fastobjects  aka decoration (speed improvment)
- adding jet reclustering code from Giovanni/Claudia
- adding METAnalyzer from susyCMG
- various cleanup and fixes