Merge pull request #5 from vetrolamu/alexg

Alexg
Merge pull request #6 from vetrolamu/alexg

Правильная привязка по id
Merge pull request #7 from vetrolamu/alexg

Locking update
Merge pull request #8 from edx/master

update from edx-platform
Revert "Merge pull request #8 from edx/master"

This reverts commit b9abf796c0e687fb77f1025d80e8f18a2167256a, reversing
changes made to 6ee483bf4b059941e06b535ad626d73652531850.
Merge pull request #15 from vetrolamu/master

update from master
change commentaries
change term display
new constructor
new constructor
Merge pull request #16 from vetrolamu/dynamic-tree

Dynamic tree