#42 Emulate3Buttons support for stylus

[Bugpunisher]

It would be very nice to have support for Xoption Emulate3Buttons. So you could have
* pen down -> left click
* pen button 1 -> right click
* pen button 2 -> double click
* pen button 1 + pen down -> middle click

Double clicking with "stylus down" only is not very reliable, because it is very hard to keep at exactly the same position via these two touches. So one is almost forced to use one of the two stylus buttons as double click. But not having a middle mouse button for moving/resizing/pasting/etc. is also not a very efficient way to work.

Having the middle button back like on an old two-button mouse would be very nice.

[Aaron Skomra]

Linuxwacom has moved from Sourceforge to Github. If this is still an issue please reopen the bug there.