Remove unused imports

Fixes compile warnings

src/angle.rs

@@ -21,7 +21,6 @@ use std::ops::*;
 
 use rand::{Rand, Rng};
 use rand::distributions::range::SampleRange;
-use num_traits::Float;
 use num_traits::cast;
 
 use structure::*;

src/projection.rs

@@ -13,7 +13,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use num_traits::{Zero, One};
+use num_traits::{Zero};
 use num_traits::cast;
 
 use structure::Angle;

src/quaternion.rs

@@ -17,7 +17,6 @@ use std::mem;
 use std::ops::*;
 
 use rand::{Rand, Rng};
-use num_traits::Float;
 use num_traits::cast;
 
 use structure::*;