typos

[Simon Albrecht]

*simon@simon-desktop*:*~/lilypond/lilypond*$ git grep mulitple
scm/define-context-properties.scm:     (subdivideBeams ,boolean? "If set, beams 
of*mulitple* stems may be
*simon@simon-desktop*:*~/lilypond/lilypond*$ git grep mulitip
scm/define-context-properties.scm:@code{beamMaximumSubdivision}, between beats 
at*mulitip*les of

I need to get back into the swing of things and will hopefully soon 
learn to make quick MRs myself. But I have to take care not to overwhelm 
myself…
Best regards,
Simon