Fix issues, comment for the list

* about and help dialog box are now ko
* erase are now disable when no graphics
* Cursor for FireFox
* Remove label 0km when dbl click measure (for windows)
* repair some WCAG issue
* blur the redo and undo after click
* text background set to green
* add missing tooltip
* scroll to opening toolbar
* new color picker
* keep panel open when user press esc to exit from text tool