New ApproxEq replaced the one in std
Fixed tests that used assert_approx_eq
Merge pull request #21 from kvark/try-approx

Reimplement ApproxEq that has been removed from the standard library
Fix renamed structures:
	VecIterator -> Items
	MutVecIterator -> MutItems
Merge pull request #25 from csherratt/Items

Fix build break
Impl appropriate operators for implementors of Zero and One
Reduce code duplication

We can now have multiple definitions in macros!
Merge pull request #27 from bjz/build-fixes

Build fixes
cargo-lite
Call rustc directly in .travis.yml
Remove unnecessary parentheses
Merge pull request #29 from bjz/travis

Call rustc directly in .travis.yml
Merge pull request #28 from cmr/master

cargo-lite
look_at() implemented as a part of Transform trait
Merge pull request #31 from kvark/try-look-at

look_at() implemented as a part of Transform trait
Fix quat::Quat::from_angle_{x|y|z}

These functions were broken due to mistakenly using the full angle theta
in one place instead of theta / 2. This resulted in non-unit
quaternions that definitely did not rotate things correctly.
Fix comments on Quat::from_angle_{x|y|z} functions
Merge pull request #33 from zhanrnl/fix-quat-from_angle

Fix quat::Quat::from_angle_{x|y|z}
Re-document build instructions in README and shorten limitations section
derive IterBytes for vectors, points, and angles

It's useful to be able to have types like `Vec3<i32>` as hashtable keys.