chore(tests): add build to allow es6 in tests

.gitignore

@@ -2,6 +2,7 @@
 node_modules
 *.log
 .tmp
+.tests
 
 # build-artifacts
 dist

.npmignore

@@ -2,6 +2,7 @@
 node_modules
 *.log
 .tmp
+.tests
 
 # source/config
 src

package.json

@@ -67,8 +67,9 @@
     "postpublish": "./bin/semantic-release.js post",
     "prepublish": "npm run build && ./bin/semantic-release.js pre",
     "pretest": "npm run build",
+    "pretest:integration": "rm -rf .tests && mkdir -p .tests && babel tests --out-dir .tests",
     "test": "./bin/test",
-    "test:integration": "tap tests/{scenarios,tap}/*.js",
+    "test:integration": "tap .tests/{scenarios,tap}/*.js",
     "test:style": "standard"
   }
 }