Refactor build system and UI

+ Install configs for Qt Designer plugins and Qtk application
+ Add Qtk plugin collection for Qt Designer
+ QtkWidget plugin
+ TreeView widget plugin
+ DebugConsole widget plugin
+ All widgets are fully integrated with Qt Designer
+ All widgets can be popped out or docked within the window
+ All widgets can be stacked to use tab view for side panels
+ All widgets can be toggled on/off through the view context menu
+ QtkWidget debug console
+ QtkWidget active scene TreeVew
+ QtkWidget dockable tool bar
+ Double-click an object name in the TreeView to focus camera
+ Separate libaray from widgets

There is still a lot to do here, but the major refactoring should be
done after this commit. Some of the new features were put together as
POC for working with the new UI. A few placeholder buttons were added
that have no functionality.

.gitignore

@@ -4,6 +4,7 @@
 # CMake build files
 **/cmake-build-debug/**
 **/build/**
+install
 
 # C++ objects and libs
 *.slo