Easier to debug, less data to transfer.

Copy over the private header files to creator source tree, along the
lines of the what the designer plugin does.

Reviewed-by: Christiaan Janssen

Reviewed-by: Christiaan Janssen

Moved qmljsdebugger to a dir under qml/, made qmlobserver compile
without creator dependencies and made it compile with debugging
helpers.

Reviewed-by: hjk

This reverts commit a9820d4f.

setEnabled(), enabledChanged() got removed in QDeclarativeDebugClient,
QDeclarativeDebugService.

This allows us to enable/disable the experimental observer, independent
from the core javascript-debugger functionality.

Reviewed-by: Christiaan Janssen

The library not only contains the observer part, but also the javascript
debugger. Reflect this in the namespace.

There is too much false exceptions that makes debugging annoying

Reviewed-by: Alessandro Portale

QMLObserver links against the library dynamically. User's apps can also
link to it statically, so that the app can be deployed with debugging
features to a device, without having to worry about library deployment.

All the expended item need to be retreived before we can call endCycle

Skip all signals and slot, there is too many of them,
and it is not usefull in the debugger.

QVariant does not work as they can contain custom type that corrypt the stream

Unfortunatelly, streaming QVariant is not a really good idea, as streaming
a custom type would fail

The agent is only attached when creator request it.  But this may occurs
After some scripts have been initialized. Which mean we do not get the
scriptLoad call.

The idea is to only enable it if it is run with -debugger, but for now
it is always enabled for simplicity.

This let you debug QML Javascript from creator