Updated all the files to compile under Rust 0.6.
Added the option of using multiple tasks for the ray tracing.
Merge branch 'master' of github.com:brson/rustray

Conflicts:
	main.rs
	math3d.rs
	model.rs
Updated to new lifetime notation, imported new RngUtil trait.
Changed const->static, switched to bufferedwriter, #[deriving_eq]->#[deriving(Eq)], and changed parse_faceindex to accept &str instead of ~str (eliminates 7x 'copy')
Changed code to use methods for Option, added lifetime for build_kd_tree.
Updated to newer version of rustc, fixed problem where multithreading would cause noticable stripes in the output image
Replaced instances of iter::repeat(num) by num.times, changed random number generation to comform to the new api
Removed unneeded mut
Updated stuff to work with newest incoming, changed the concurrency to be slightly less silly. It seems to have gotten faster too.
Removed some unnecessary allocations, renamed std->extra, core->std
Updated README.
Including std::* in most files to get stuff working again.
Removed a few instances of #[inline(always)], removed several pointless 'f32' and 'u' postfixes.
Minor changes to compile with incoming/HEAD once more
Moved from .each to .iter().advance
Changed instances of 'vec += [something,somethingelse]' to 'vec.push(something);vec.push(somethingelse)'
Replaced vec::map function with the method equivalent.
Removed instance of vec::consume
Updated to use .min, .max, .cos, .sin, .tan, and .sqrt methods instead of functions.
Minor cleanup.