splay tree and red-black tree for vm_map entry lookups.

[Matthew Dillon]

    Well, I haven't been able to figure out why the hinting code
    doesn't work.  I am going to do some overnight testing without it,
    plus a few other minor cleanups, and if the machines survive I'll
    commit it tomorrow morning so it can get wider testing.  I will also
    commit that filesystem inode patch tomorrow morning if testing goes 
    well.

    I'm really intrigued as to why the hinting code doesn't work.  There's
    something fundamental that is being missed here.

						-Matt