sampleGibbs start to support multiple targets

sampleGibbs.m
- multiple targets are tried, targets are taken to be
  the same as Jones (2001) has
- instead of absolute values, difference between maximal and minimal
  fitness should be taken, not final version!
gpeda.m
- best individual saved even from the initial population
- current attempt struct is passed to the sampler
gpedaStep2D.m
- graphical output is more clear
Merge remote-tracking branch 'origin/master'

Conflicts:
	src/gpeda.m --  only update of auxiliary output
                        of current best solutions