Version 2.0-libre-33 uploaded

I uploaded version 2.0-libre-33 (i.e. 33 git commits after tag 2.0-libre). This version includes the following changes:

• A lot of code was reworked to accommodate Qt5.3 and the issue of Glew compatibility. So now I can build with Qt5.3 on all platforms, including Windows.

• Fixed a bug with drag operations which amplified your movement by a factor of 2. This was a side effect of the two-pass drawing introduced to handle transparency better.