[trunk] Beaming issues when reading score created with 0.9.6

Tested with r. 3251 under Ubuntu Karmic.

Open with the trunk version a score created with 0.9.6, for instance the one attached.

Result:
* In 4/4, runs of 8ths and 16ths are all beamed together, while with 0.9.6 they were shown grouped (almost) correctly
* in 6/8, 8ths are beamed by two instead of by three.

* Strangely, when the notes are copied from existing 0.9.6-created score into a new score, they are beamed correctly (as well as when they are re-typed from scratch).

Expected result:
Flagged notes are beamed as in 0.9.6

A sample screen shot is also attached showing two sample cases in 3 contexts:
* as shown by 0.9.6
* as shown by trunk
* as shown when copied from existing score into new trunk-created score.

M.