Re: \markup \sans ... does not always give sans-serif output in svgs in 2.19.36

[Paul Morris]

Looking closer at the SVG files produced...  In 2.18 we have this:

  <text … font-family="sans-serif” … > some text </text>


Whereas in 2.19 we have this:

  <text … font-family="LilyPond Sans Serif” … > some text </text>


And when I manually edit the 2.19 svg file so it has font-family="sans-serif” 
then that fixes it and the text appears as sans-serif.  Elsewhere in the svg 
files I see that:

2.18 svg has:  font-family="Century Schoolbook L”
2.19 svg has:  font-family="LilyPond Serif"

From this thread:
http://lists.gnu.org/archive/html/lilypond-devel/2015-06/msg00175.html

and this commit:
http://git.savannah.gnu.org/gitweb/?p=lilypond.git;a=commit;h=28f58ecc2271956e9377dc61e5135ce3ade4abbd

we see that “LilyPond Sans Serif” and “LilyPond Serif” are aliases.  So it 
appears that the code that produces the svgs is including the alias names for 
“font-family" rather than what the alias refers to (e.g. “sans-serif” or 
"Century Schoolbook L”).

-Paul