Delete core, move "api" directory up to "src", and remove unused dependencies

package.json

@@ -15,23 +15,17 @@
     "test": "test"
   },
   "dependencies": {
-    "async": "~0.9.0",
     "babel-runtime": "^5.5.4",
     "bignumber.js": "^2.0.3",
-    "bn.js": "^3.1.1",
-    "extend": "~1.2.1",
     "hash.js": "^1.0.3",
     "https-proxy-agent": "^1.0.0",
     "is-my-json-valid": "^2.12.2",
     "lodash": "^3.1.0",
-    "lru-cache": "~2.5.0",
     "ripple-address-codec": "^2.0.1",
     "ripple-binary-codec": "^0.0.6",
     "ripple-hashes": "^0.0.1",
     "ripple-keypairs": "^0.10.0",
     "ripple-lib-transactionparser": "^0.5.1",
-    "ripple-lib-value": "0.1.0",
-    "sjcl-codec": "0.1.0",
     "ws": "~0.7.1"
   },
   "devDependencies": {