Issue 3911: Two minor fixes in pondings

Fix typo in ponding
Indentation fix in ponding
corrects typo in bar-line.scm

issue 3908

Missing space in (define-bar-line ":|]" ":|]" #f " |") caused bad
visual output of VoltaBracket.
Changed to (define-bar-line ":|]" ":|]" #f " | ")
The space added will cause that the SpanBar x-extent will be calculated
correctly to determine the gap between two VoltaBrackets.
CG: Updated Minor Release Checklist

To include the changing of the \version number of the two

Welcome* files in the ly directory

Currently this is hard coded.
Issue 3913: KeyCancellation grobs should ignore cue clefs like KeySignature grobs do

For

{
  \key f \major R1 \cueClef bass \key g \major R1 \cueClefUnset
  R1 \cueClef alto \key bes \major R1
}

the cancellation signs for the key changes were erroneously placed in
reference to the current cue clef rather than the main clef while the
key signature itself was properly unimpressed.
Issue 3912: New Ponding: Urs Liska Berne lectures
mf: Set FONTFORGE environment variable while calling `mf2pt1' (#3914).

Otherwise the script takes the first binary found in the path, regardless of
the value used while calling `configure'.
Release: bump VERSION_DEVEL.
PO: update template.
Release: update news.
Release: bump Welcome version
Release: bump VERSION.
Web: Update News Typo fix

Minor line break adjustment as per CG
Fix calculation of X-extent of AccidentalPlacement.

Previously, the offsets used for staggered placement of accidentals
were not included in the calculation of the width of AccidentalPlacement
grobs.
Merge branch 'origin/master'