Extended intrinsic functions support.

Support get_property according to latest spec.
Support get_input.
Support recursive functions.
Process intrinsic functions in node template properties, interfaces,
capabilities and requirements.
Initialize node template properties and interfaces only once.
Removed inline importing of NodeTemplate in functions module.

Implements: blueprint tosca-ref-property

Change-Id: I363e1cc27791e6991d7e586c4e012b7ceed94490
Merge "Extended intrinsic functions support."