Hi,
I've added a dependency to libGLEW to current master. I wanted to implement libglew support for a while but feared it would break things, it turned out to be almost trivial.
Now travis-ci wont break anymore because I use an extension not declared in mesa/OSX and thus it brings OpenGL parity between Windows and Linux (I previously disabled features on Linux at compile time)
For linux use your package manager to install libglew-dev(el), for Windows I've attached a zip containing libGLEW dependency files, to put in the dependencies folder.
It's from the official libGLEW binary provided here : http://glew.sourceforge.net/
Vincent