Mirror HUD example

[mcclure]

Here is an example of a simple program that uses HUD and a mouse. Click on the grid to create or destroy vertical boxes. The idea is one person can be in VR and the other person is "editing" the space they're in.

Things that should change before this is checked in:

• Most significant: This either has a bug in its mesh code or exposes a bug in Lovr's mesh code. If you comment out triangle:draw() it works, if you leave it in the drawing freaks out
• I want to switch to using Lovr vectors throughout
• Have not tested on hardware
• I wish it only showed one eye in the HUD window instead of both eyes
• I want to comment it

Stray thought:

• It would be SORTA nice if there were some way to address the "jump" in mac fake, or if clicks inside the grid were "eaten"

[mcclure]

This is ready to be merged I think. The glitch graphics bug is fixed with current master and there are comments in. I don't think after all I should switch to Lovr vectors because most of the vectors are 2-vectors and probably using Lovr's current 3-vectors to simulate 2-vectors will be no less confusing than just doing x,y separately as I do here.

Note, I never did test this on real hardware.

[bjornbytes]

There is 1 more bug on real hardware (known bug, this is the first app to encounter it) that I'm going to fix before merging.

Also, our GLFW is 2 years old, I am trying to upgrade it to see if it fixes the jumpy mouse.

[bjornbytes]

Merging this finally!