Matt ayman frames

Redo of the merge of Frame, RigidFrame, FixedFrame, Station and Marker ModelComponents along with code to convert Marker to new format for serialization/deserialization and inclusion of FrameSet in model.
@sherm1 @msdemers @aseth1 or @chrisdembia Please review and let us know your feedback.
Connections have connectionType=Frame and connectionName="reference_frame". The naming is consistent with how @aseth1 uses "parent_body" and getParentBody() for Joint. Which is the only use case for connections so far. We can change the "connectionName" to just "frame" and use set/getFrame  though it's a bit less descriptive.