QT5 -- 1 of 3

Porting the codebase to QT 5 (5.2) to get the
latest bug fixes, performance and improved platform
support.

This first part is to fixup the codebase to compile
on Qt 5, but some aspects have been broken (video).

The second part is to migrate from Qwt 6.0.1 to the
latest Qwt for multiaxis support.

The third part will be to fixup any platform specific
issues or issues identified at runtime.
QT5 -- remove old qwt
QT5 -- Add Qwt 6.1-multiaxes
QT5 -- QWT 6.1 canvas fixup
QT5 -- 2 of 3

Fixup all the GC code to use the QWT 6.1 code.
It needed canvas() to be patched to return a
QwtPlotCanvas and not a QWidget.

We could probably get round that with a cast.

When we switch to QWT 6.2 with the multiaxis
support formally baked in we can fix the code
as needed.

Now compiles and links without issues.
QT5 -- Part 3 of 3

Fixup crashes and major issues created by porting
to QT5. These have included;

* Fix CP plot log scale
* AllPlot axes and tooltip
* DBAccess prepare/bind bug
* LTMSettings crash
* LTMWindow zoomer/picker crash
* LTMPlot axes hack

There are still issues remaining but we can start
working through them at leisure -- the product now
builds and runs.