More consistent with Qml usage pattern

Also many LinkManager API changes to further isolate all link
management inside LinkManager.

If it doesn’t exist it will be prefilled with all registered categories
set to false

FactTextField, when setting the value from its "text" field, was converting the value to string. This was causing (QML JavaScript) code that uses the value for computation to stop working once the user changed the value.

Also changed to qWarning

Passing parameters QVariantMap across C++ boundary was causing crashes
in Qt due to Qml array bugs. Referencing same Fact* across Qml boundary
in multiple QQuickWidgets caused jScript GC to crash.

Since this is generic Qml support not specific to FactSystem

- properties now hand off of main “autopilot” object in qml
- Added support for summary items through qml

This way you don’t need to know parameter set ahead of time.

Plus a large number of other changes to allow for orderly shutdown of
objects without crashes or asserts. This is need for unit tests to
create/delete global state around every test.

Allows parameter access from QML among other things