Remove an exceedingly pointless copy from CompositeTransform
Superclass init methods are not called automatically
Consider timeVarying status of child transforms in pipe project

In the train loop, consider timeVarying in addition to trainable.
When setting up partial projects, stop at timeVarying stages in addition to
trainable stages. Call projectUpdate (with the full training set) on
timeVarying stages.
Merge pull request #81 from biometrics/pipe_changes

Changes to Pipe::train