Comment 17 for bug 170498

Hi, I just add a branch to the bug to allow arbitrary rotate of document.
The rotation become in the middle of the display area, so good to tablet users.
I add also the fix to the png export, an small change easy to migrate to other exports.
To view working you need to update the new namedview parameter inkscape:rotation.
Todo:
* fix doc undo.
* Apply png code to other outputs.
* Make a GUI to this parameter.

Feel free to try and send me feedback!