decision_tree 6.x-1.0-beta1

First release, should be working with these features:
- unlimited number of decision trees (terms in DT vocabulary)
- any question can be included into any decision tree (just assigned a term from DT vocabulary)
- question is a content type with any number of answers (CCK field)
- questions can be boosted (assigned a boost factor - CCK field - to force it to appear earlier in the tree)
- any content can be included into any decision tree (just assign answers to questions for the decision tree)
- any content can be temporarily excluded from any decision tree (but keeping the answers in the DB)
- showing decision tree branches weights (how many content items are under this answer to this question placed on this spot in decision tree) for administrators ('administer decision tree' permission)

This release doesn't have any tools to analyze decision trees (meaning the big ones). Still looking for good info on what metrics and analytical tools to provide.