Add missing examples from the website.

examples/cargo/Cargo.toml

@@ -0,0 +1,11 @@
+[package]
+name    = "example-using-nalgebra"
+version = "0.0.0"
+authors = [ "You" ]
+
+[dependencies]
+nalgebra = "0.11.0"
+
+[[bin]]
+name = "example"
+path = "./example.rs"

examples/point_construction.rs

@@ -0,0 +1,26 @@
+extern crate nalgebra as na;
+
+use na::{Vector3, Vector4, Point3};
+
+
+fn main() {
+    // Build using components directly.
+    let p0 = Point3::new(2.0, 3.0, 4.0);
+    
+    // Build from a coordinates vector.
+    let coords = Vector3::new(2.0, 3.0, 4.0);
+    let p1 = Point3::from_coordinates(coords);
+    
+    // Build by translating the origin.
+    let translation = Vector3::new(2.0, 3.0, 4.0);
+    let p2 = Point3::origin() + translation;
+    
+    // Build from homogeneous coordinates. The last component of the
+    // vector will be removed and all other components divided by 10.0.
+    let homogeneous_coords = Vector4::new(20.0, 30.0, 40.0, 10.0);
+    let p3 = Point3::from_homogeneous(homogeneous_coords);
+    
+    assert_eq!(p0, p1);
+    assert_eq!(p0, p2);
+    assert_eq!(p0, p3.unwrap());
+}