Throuw background error when running with virtual sites and having non-consecutive particle numbering
Change warning to error in part n vs_auto_relate_to
Mentioned the pressure contribution for vs_relative and the need for consecutive particle numbering when using vs in the manual.
Added access to particle charge in the python interface
Only compile python iface to debye hueckel, if ELECTROSTATICS is on
Fix Virtual sites test case
Merge branch 'master' of git://github.com/espressomd/espresso

Conflicts:
	NEWS