Added XmlParser and Metadata support.
Minor changes.
Added non-deterministic support to BranchNode.
Improved behavior tree language and rewritten the parser with Ragel.
Minor change
Added BehaviorTreeLoader for asynchronous loading.
Fixed BehaviorTreeLoader.
Clone capabilities added and tests reorganized.
Added missing test.
Added behavior tree library, subtree reference nodes and tests.
Minor change.
Lazy and eager subtree inclusion is now implemented as a single
decorator.
Minor change in tests.
Improved BehaviorTreeLibrary with generics.
Fixed missing error checking on the last line.
Minor changes.
Removed debug println.
Now '?' is a legal char for task aliases (useful for conditions).
Refactoring: replaced node with task in class names and variables.