Merge pull request #42 from bvssvni/master

Renamed `clear_shader` to `clear_program`
Merge pull request #43 from bvssvni/master

Simplified shader parameters
Merge pull request #44 from bvssvni/master

Simplified shader parameter
Merge pull request #45 from bvssvni/master

Removed unnecessary "tri_list"
Merge pull request #46 from bvssvni/master

Removed "tri_list" prefix
Merge pull request #49 from bvssvni/master

Added update function
Merge pull request #50 from bvssvni/master

Added from_image
Changed to 150 core

Closes https://github.com/PistonDevelopers/opengl_graphics/issues/52