For bug #7191.
Improvements to the dialog that sets up the first configure.
Fixing the large size of it by breaking it up into a wizard.
Also incorporated suggestions from bug report.
the generator on the first configure. It either ask for a toolchain file
or asks for all the information a toolchain file might contain.
Also added option for setting non-default compilers if not cross compiling.
Fixes#6849.
Also a bit of code cleanup and re-organizing.
Implement help button.
Implement cancel button.
Add scrollable output window.
Replace ON/OFF & combobox editors with checkboxes.
Tab/backtab in cache table jumps between values (not names and values)
Add tooltips to show help strings.
Add application icon and qtmain for Windows.
BUG: Fix save of cache values on configure.