Contains speed optimizations, mostly by reducing the number of promise created.
This reduce the garbage collection load.

Add mutex support in declareMethod.

Fix a memory leak.

Iframe: ensure all channels are OK before calling ready

Do not update jslint version which deprecates indentation options.

Add onLoop service.
Allow manualBootstrap.

onStateChanges bug fixes

Nearly drop iframe timeout.
Add reportGadgetDeclarationError acquired method.

Performance improvements.

* add an internal gadget state
* rename __element property to element
* add declareJob function
* add onEvent method
* 'this' in ready is now the gadget instance InlineSide-by-side

Improve error verbosity

Do not prevent calling declareGadget in ready functions.
Allow to directly declareGadget inside the HTML.

Drop EventTarget support on Gadget.
Add declareAcquiredMethod, allowPublicAcquisition.
Prefix attribute non part of the API by __. Such method/property can be rename
in next versions without any compatibility support.
Use base element in iframe to get the same link behaviour with or without
iframe.

Display the error in the console.