Merge pull request #32 from Coeuvre/master

Upgraded to latest rust-image
Fixed Cargo issues

* Ignoring Cargo.lock
* Removed unused readme field in Cargo.toml
Merge pull request #34 from bvssvni/master

Fixed Cargo issues
Added docs about `GenTextures`

Closes https://github.com/PistonDevelopers/opengl_graphics/issues/37
Closes https://github.com/PistonDevelopers/opengl_graphics/issues/36
Merge pull request #38 from bvssvni/master

Added docs about `GenTextures`
Update Travis CI
Merge pull request #39 from Indiv0/update-travis-ci

Update Travis CI
Add Rust-ci to Travis

Change after_script to after_success
Merge pull request #40 from Indiv0/add-rust-ci-to-travis

Add Rust-ci to Travis
Temporary fix for rust-ci
Merge pull request #41 from Indiv0/fix-rust-ci

Temporary fix for rust-ci
Renamed `clear_shader` to `clear_program`
Merge pull request #42 from bvssvni/master

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

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

Simplified shader parameter
Removed unnecessary "tri_list"
Merge pull request #45 from bvssvni/master

Removed unnecessary "tri_list"
Removed "tri_list" prefix