Change find() to return a slice, rename old find to find_mut
Implement find_mut using the new find()
Add a benchmark for find_mut
Merge branch 'master' into lifetimes
Merge branch 'master' into lifetimes
Remove deprecated Vec::from_slice()
Merge branch 'master' into lifetimes
Merge branch 'master' into lifetimes

Conflicts:
	src/base.rs
fail! --> panic!
Merge branch 'master' into lifetimes
Merge branch 'lifetimes'