[WebProfilerBundle] Improved JavaScript of the form debugger
[WebProfilerBundle] Inverted toggler images and improved button coloring
[WebProfilerBundle] Added "use strict" statements
[WebProfilerBundle] Changed toggle color back to blue and made headlines in the form debugger clickable
[WebProfilerBundle] Moved toggle icon behind the headlines in the form debugger
[WebProfilerBundle] Enlarged the clickable area of the toggle button in the form tree