replace babel-preset-es2015 with babel-preset-env for deprecation

add babel-plugin-transform-object-rest-spread for spread syntax support
add test to cover spreading composed into object.

Author: mringer

.babelrc

@@ -1,4 +1,5 @@
 {
-  "presets": ["es2015"],
-  "sourceMaps": true
+  "presets": ["env"],
+  "sourceMaps": true,
+  "plugins": ["transform-object-rest-spread"]
 }

package.json

@@ -36,7 +36,8 @@
     "babel-cli": "^6.18.0",
     "babel-core": "^6.17.0",
     "babel-eslint": "^7.0.0",
-    "babel-preset-es2015": "^6.16.0",
+    "babel-plugin-transform-object-rest-spread": "^6.26.0",
+    "babel-preset-env": "^1.7.0",
     "babel-register": "^6.18.0",
     "bluebird": "^3.5.0",
     "chai": "^3.5.0",

test/unit/helper_spec.js

@@ -323,13 +323,15 @@ describe('(unit) src/helper.js', () => {
       const comp = base.compose({
         r1: { resolve: () => { throw Error('some other error') }, error: () => compositionErr },
         r2: { resolve: () => 'r2Result', error: () => compositionErr },
-        r3: {} // should this throw an exception since it is not a resolver or createResolver params?
+        r3: {} // should we throw an exception since it is not a resolver or createResolver params?
       });
 
-      console.log(typeof Function);
-      expect(comp.r1).to.be.a(typeof Function);
-      expect(comp.r2).to.be.a(typeof Function);
-      expect(comp.r3).to.be.a(typeof Function);
+      const composed = { r0: () => {}, ...comp };
+
+      expect(composed.r0).to.be.a(typeof Function);
+      expect(composed.r1).to.be.a(typeof Function);
+      expect(composed.r2).to.be.a(typeof Function);
+      expect(composed.r3).to.be.a(typeof Function);
 
     });