Generalized rolling

[arrdem]

This PR reworks the roll extension system, documents Katamari's build model and attempts to implement statically dependent, topologically ordered builds with the slight modification that during the prep step, rules and manifests have the opportunity to inject dependencies and rules not explicitly declared in a Rollfile.

TODO:

• [x] rework the clojure-library manifest to produce a build result with {:deps ..., :paths ..., :classpath ..., :libpath ...}.
• [x] implement the java-library manifest using deps for java dependencies, and producing the same product structure as clojure-library.
• [ ] rework the classpath task to consume either a clojure-library or a java-library and print the resulting :classpath.

If that can be proved out then separately a test task and clojure-test manifest can be added easily enough.

[arrdem]

$ ./kat compile example/clj+uberjar
{
  "example/javac": {
    "type": "katamari.roll.extensions.jvm/product",
    "from": "example/javac",
    "mvn/manifest": "roll",
    "deps": null,
    "paths": [
      "/private/var/folders/z4/6b9f3h4x2dv6gvxbwyc55cwnwhsd5r/T/javac6828446538002526748"
    ]
  },
  "example/clj": {
    "type": "katamari.roll.extensions.clj/product",
    "from": "example/clj",
    "mvn/manifest": "roll",
    "paths": [
      "/Users/arrdem/katamari/example/src/main/clj"
    ],
    "deps": {
      "example/javac": null,
      "org.clojure/clojure": null
    }
  },
  "example/clj+uberjar": {
    "type": "katamari.roll.extensions.jar/product",
    "from": "example/clj+uberjar",
    "mvn/manifest": "roll",
    "paths": [
      "/Users/arrdem/katamari/target/clj-standalone.jar"
    ],
    "deps": {
      "example/javac": null,
      "example/clj": null
    }
  },
  "intent": "json"
}

It's all working!