Changes from MusiXTeX 117 to 118:

2015-07-25

  moved definitions of \raggedstoppiece and \slide 
     from musixtext.tex to musixtex.tex.
  \xppff musicsize-dependent as well as staffsize-dependent
  revised musixtmr.tex, musixplt.tex and musixhv.tex to allow
    traditional accented characters for etex
  increased the length of beam stems