Merge branch 'master' of ssh://jomand@git.sv.gnu.org/srv/git/lilypond
* 'master' of ssh://jomand@git.sv.gnu.org/srv/git/lilypond:
GDP LM 3.3.4 Explaining \context
Updates to chords.itely, fretted-strings.itely
Compile fix.
Update from Kurt.
Update fretted-strings.itely
staff-symbol-referencer.cc: Junk redundant functions.
Robustify Staff_symbol_referencer::on_line ().
Update fretted-strings.itely
Change type predicate for 'layer to integer.
Replacing "User Manual" with "Notation Ref" in SL