Merge pull request #1 from kuz/master

Typos in 03-Triangles
Fixed problems with linux projects for Practice03
Lecture 4
Merge branch 'master' of github.com:konstantint/ComputerGraphics2013
Practice session 04
Linux project files
Added note for Linux users
Added exercise to p04
Lecture 5
Removed typo in practice 04
Practice session 05
Downgraded to GLSL V1.2 to support VirtualBox-ed systems
Fixes for running OpenGL samples in Virtualboxed Ubuntu
Practice 05 Linux project files
GLEW dll got corrupted for some reason
Additional remarks for Practice 05 text
Minor fixes
Removed forgotten code line
Demo app for lecture 05
Changes to the lecture demo app