Can't enter several stereotypes for attributes/operation in diagram editor in
platform independent project.

steps:
1. create platform independent project
2. add class diagram
3. put class
4. add operation
5. move cursor left and press '<'
6. edition of stereotype should start
7. check tooltip, it shows you can enter 'stereotype1,...'
8. try to type 'a,b' stereotypes
',' is not accepted, can't enter several stereotypes
9. add attribute
10. move cursor left to visibility
11. press '<'
12. type 'a,b' for stereotypes
it's possible
13. add attribute
14. add several tagged values to second attribute
15. try to add 'a,b' srtereotypes to second attribute 
',' move cursor to tagged values