Regtest 2.17.13

[Phil Holmes]

I've run my pixel comparator on 2.17.13 versus 2.17.12 (note - the output 
shows this as 2.17.11 since the windows exe contained the wrong version 
number).  Output is at

http://philholmes.net/lilypond/regtestresults/2.17.13/

As might be supposed, most of the differences are connecting bar lines. 
However, I've put them all there so that David can check for any other 
problems.  There are one or two oddities - stem length, flag markup and 
tablature, so it would be worth other devs glancing over them.  Note that 
one image is _very_ wide, so please scroll right for filename and any 
comment I may have included.

--
Phil Holmes