Having some interactive elements forces the screen readers to switch to form mode
and consequently they delegate the keyboard stuff to the browser.
This patch sets an aria label on each editor in order to have a better description than just
'application'.
The idea is to avoid to have the pasted editor hidding the copied one:
the user could think that nothing happened.
So the top-left corner of the pasted one is moved to the bottom-right corner of the copied one.
This patch fixes an issue when pasting: an exception was thrown when pasting.
And while writing the test and comparing the paths in the svg, I found a difference
which is fixed thanks to call to the right constructor (to take into account the inheritance)
in inkdraw.js
