Also print 1x1 pair-list setup to log

Also print 1x1 pair-list setup to log

mdrun now prints the equivalent 1x1 pair-list setup in addtion
to the NxM list setup. This is to clarify that we can use short
pair list buffers because of our cluster setup.
The list setup is now also printed in case we have a single list.
Removed the note on needing to increase nstlist with a GPU when
we automatically change nstlist.
Changed pick_nbnxn_kernel and nbnxn_atomdata_init to use mdlog
to get correct spacing between paragraphs.

Also cleaned up the verletbuf list setup getter functions.

Change-Id: Ic7b5967b0a62aee9fee9837f60a134fd571ff405