Sorted dict 1

Pull request for SortedDict and BalancedTree23 taking into account Kevin Squire's feedback from the past 12 days.
Kevin,

This is just to let you know that in a very recent build of Julia 
(0.4.0-dev+952, Commit 592ec62), the test files in DataStructures.jl for 
defaultdict, ordereddict and orderedset are all crashing with 
InexactError().  I am not working on any of those data structures myself.

-- Steve


On Mon, 15 Sep 2014, Kevin Squire wrote:

> 
> In src/balancedTree.jl:
> 
> > +                      p::Int, sk1::K, sk2::K)
> > +        new(c1, c2, c3, p, sk1, sk2)
> > +    end
> > +end
> > +
> > +
> > +
> > +## The next two functions are called to initialize the tree
> > +## by inserting a dummy tree node with two children, the before-start
> > +## marker whose index is 1 and the after-end marker whose index is 2.
> > +## These two markers live in dummy data nodes.
> > +
> > +function initializeTree!{K}(tree::Array{TreeNode{K},1})
> > +    resize!(tree,1)
> > +    tree[1] = TreeNode{K}(K, 1, 2, 0, 0)
> > +end
> 
> Consider returning either tree or nothing here. Currently, this returns the newly created
> TreeNode.
> 
> —
> Reply to this email directly or view it onGitHub.[7881863__eyJzY29wZSI6Ik5ld3NpZXM6QmVhY29uIiwiZXhwaXJlcyI6MTcyNjQ2NjA1MiwiZGF0YSI6eyJpZCI
> 6NDE3MzQ5Mjl9fQ==--4080e47e1e1ca4aba362f2cd7ff2d0b69b29e8ac.gif]
> 
> 
>