Added a workaround to combine LB and VS_RELATIVE

After propagating the virtual sites, the cell lists have
to be updated, so that they are contained in the correct cell.
If not, there might be no corresponding LB cells (also in the halo)
that allow to calculate the particle-lattice-interaction.
Merge branch 'master' into HEAD

Conflicts:
	src/communication.c
	src/lb-boundaries.c
	src/lb-boundaries.h
	src/lb.c
	src/lb.h
Started writing user guide for correlations
added block-averaged observable com_pos and com_vel

This will probably be generalized soon, but however, it might
be a helpful start
Merge branch 'timecorr', remote branch 'peter/timecorr' into timecorr
Bugfix: calling update now checks for autoupdate.

Further changes to user guide on correlations.
Observable "new" + Changes to ug + Bugfix

1. Implemented the observable new ... command in analogy to
   correlation new.
2. Changes to the documentation of correlations and observables
   based on comments of Petra Bacova.
3. Bugfix: each time observable [id] was called, space for one more
   observable was allocated irrespective of what the call was.
micro error removed
Bugfix: write 6 significant digits, not 6 decimal places when calling correlation write_to_file
1. Implemented printing of correlation parameters (incomplete yet).

2. Moved all consistency checks of correlation arguments to double_correlation_init()

3. Removed corr_type from the correlation struct.

4. Implemented some more coditional correlations and observables
added axels statistics file
Merge branch 'master' into timecorr

Conflicts:
	src/communication.c
	src/lb-boundaries.c
	src/lb.c
Merge branch 'timecorr' of https://github.com/kosovan/espresso into timecorr
removed included picture that was still not on git

but only on peters computer
included automatic calculation of induced charges

It is now done at the beginning of every integration step.
removed debug output
added testcase for iccp3m
added convenient commands for dielectric interfaces

The pore dielectric still does not work ....
improvements of the dielectric_pore
dielectric_pore and pore constraint consistent

Still a bit of debug output to reproduce plots of the shape.