node-sass should be update to 3.7.0

[lihuazhang]

node-sass should be update to 3.7.0, or it will throw ObjectTemplate::Set() with non-primitive values is deprecated exception. see sass/node-sass#1484

and when run build, it will throw

> redux-webpack-es6-boilerplate@0.7.1 build /Users/lihuazhang/code/React/redux-demo
> SET NODE_ENV=production & NODE_ENV=production & webpack -p --config ./config/webpack.config.prod.js --progress

sh: SET: command not found

so

diff --git a/package.json b/package.json
index 2a77f87..48c968b 100644
--- a/package.json
+++ b/package.json
@@ -26,7 +26,7 @@
     "prestart": "node ./bin/clean.js",
     "start": "webpack-dev-server --config ./config/webpack.config.dev.js --hot --inline --progress",
     "prebuild": "npm run clean:build && npm run build:html",
-    "build": "SET NODE_ENV=production& NODE_ENV=production& webpack -p --config ./config/webpack.config.prod.js --progress",
+    "build": "export NODE_ENV=production & NODE_ENV=production & webpack -p --config ./config/webpack.config.prod.js --progress",
     "lint": "eslint config src/js/** --ext .js",
     "jscs": "jscs src/js/",
     "test": "mocha --compilers js:babel-core/register,css:./test/unit/cssNullCompiler.js --require ./test/unit/testHelper.js --recursive ./test/unit",
@@ -53,7 +53,7 @@
     "jscs": "2.10.1",
     "jsdom": "8.2.0",
     "mocha": "2.4.5",
-    "node-sass": "3.6.0",
+    "node-sass": "3.7.0",
     "postcss-loader": "0.8.2",
     "react-addons-test-utils": "15.0.1",
     "react-hot-loader": "1.3.0",

[nicksp]

@lihuazhang Thanks for you advice. Applied suggested changes. Gives me no errors now.
You can pull latest changes now.