Fix beamlet pointing wrong way when tuplet 16th beamed with 8th (issue 2113) (issue 5495076)

[k-ohara5a5a]

Maybe just restore the old tests (from before the issue 11 fix) with the
comment
 //Try to avoid sticking-out flags



http://codereview.appspot.com/5495076/diff/1/lily/beaming-pattern.cc
File lily/beaming-pattern.cc (right):

http://codereview.appspot.com/5495076/diff/1/lily/beaming-pattern.cc#newcode104
lily/beaming-pattern.cc:104: return (infos_[i].rhythmic_importance_ <
infos_[i + 1].rhythmic_importance_)
If this fixes the reported bug then,
1) the triplet 16th has the same rhytmic importance as the 8th note,
which seems odd
2) it won't fix the case where the timing is the other way
{ \times 2/3 { b16 b b } b8 b4  b8 \times 2/3 { b16 b b } b4 }

http://codereview.appspot.com/5495076/