Fix null pointer access.
Replace old port registration interface with port existence and requirement, fix Device implementation init interface.
Check device port requirements on Handle validation.
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Create connections between existing ports only.
Add port manifests to libkunquat tests.
Add reader functions for port manifests.
Add port manifests to example files.
Share common code among effect/DSP reader callback functions.
Check during validation that all device connections are between existing ports.
Disable obsolete tests.
Remove port requirement tracking inside devices.
Add top-level master output port manifest reader.
Add top-level master output port manifests to libkunquat tests.
Add top-level master output port manifest to the example composition.
Create top-level output port manifest when creating default composition in the tracker.
Merge pull request #275 from kagu/port_manifests

Port manifests