add glyphs

+ s
+ t
+ r

Maybe a fix for weird contrast in glyph u
debug oblique serifs + new glyphs

debug on glyph x
+ add _E
+ add D
+ add z
+ add x

+ modif some glyphs
add glyphs

+ F
+ G
+ I
add glyphs

+ R
+ P
+ N
+ O
+ L
order sliders
Merge branch 'new_glyphs' of github.com:byte-foundry/prototypo into fix_#11
tabbed parameters!