Mixin DependencyAPIMigration to all Transforms

This mixes in the new DependencyAPIMigration trait into all Transforms
and Passes. This enables in-tree transforms/passes to build without
deprecation warnings associated with the deprecated CircuitForm.

As a consequence of this, every Transform now has UnknownForm as both
its inputForm and outputForm. This PR modifies legacy Compiler and
testing infrastructure to schedule transforms NOT using
mergeTransforms/getLoweringTransforms (which rely on inputForm and
outputForm not being UnknownForm), but instead using the Dependency
API.

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@ibm.com>