Bundling up args from `Workspace` to `World` in a `MiniWorkspace`
Allowing engine code to run with a swapped-in auxiliary RNG

This is needed by widgets (e.g. monitors, plots) for
non-deterministically calling code that changes RNG state without
breaking run reproducibility.

The current solution is temporary and ought to be superseded later by
one that properly passes the RNG through a call context (along with
`self`, `myself`, and probably the current plot and plot pen).
Fixing color cache computation
Adding engine code for plotting
Adding concept of a "model config", hooking up plotting through it

Updating ALL THE DUMPS
Hooking up plotting primitives to the new, respective engine code
Adding tests for dem dere new-fangled plotting prims
Adding mouse prim support
Doing a better job of storing a plot's info
Updating dumps for new plotting config
Ensuring that `clear-all` calls `clear-patches` (fixes #107)

This was actually a pretty neat bug.  Looks like, back in f8533aa, the
intended code in the implementation of `clear-all` was `clearPatches`,
but `createPatches` was typed instead, and it worked fine, given the
state of the engine at the time.  However, when I implemented patch
neighbor caching in fa1fa80, the crouching tiger beetle/hidden dragonfly
leapt from the shadows and struck!  This is because the `Topology` was
keeping a cache of patches, but, after `world.createPatches`, the cached
patches were no longer in the set of patches being tracked by the
`World`.  Subtle.

Oh, also in this commit is a dependency on a new version of Headless,
which contains a test that failed before this commit and now passes.
Making the evil, trouble-making `World.createPatches` private
Caching link array for speedup
Clean up and optimize Breed.add and Breed.remove
Merge pull request #108 from NetLogo/breed-add-remove-opt

Clean up and optimize Breed.add and Breed.remove
Tweaking
Sanitizing plot axis names
Updating dumps
upgrade to Scala 2.11.4
Merge pull request #110 from NetLogo/scala-2.11.4

upgrade to Scala 2.11.4