我按照这里的说明在Windows7上安装ionic，但出现了错误。

当前安装的其他实用程序版本是：

nodejs version 4.3.1

npm version 2.14.12

cordova version 6.0.0

当我尝试安装ionic时，得到以下结果

C:\Users\pranav>npm install -g ionic

npm WARN deprecated gulp-minify-css@0.3.13: Please use gulp-cssnano instead.

npm WARN deprecated graceful-fs@3.0.8: graceful-fs version 3 and before will fail on newer node releases. Please update to graceful-fs@^4.0.0 as soon as possible.

npm WARN deprecated npmconf@2.1.2: this package has been reintegrated into npm and is now out of date with respect to npm

npm WARN deprecated lodash@1.0.2: lodash@<3.0.0 is no longer maintained. Upgrade to lodash@^4.0.0.
npm WARN deprecated graceful-fs@1.2.3: graceful-fs version 3 and before will fail on newer node releases. Please update to graceful-fs@^4.0.0 as soon as possible. > spawn-sync@1.0.15 postinstall C:\Users\pranav\node_modules\ew\node_modules\gulp-sass\node_modules\node-sass\node_modules\cross-spawn\node_modules\spawn-sync > node postinstall /

node-sass@3.4.2 install C:\Users\pranav\node_modules\ew\node_modules\gulp-sass\node_modules\node-sass

node scripts/install.js Binary downloaded and installed at C:\Users\pranav\node_modules\ew\node_modules\gulp-sass\node_modules\node-sass\vendor\win32-ia32-46\binding.node > node-sass@3.4.2 postinstall C:\Users\pranav\node_modules\ew\node_modules\gulp-sass\node_modules\node-sass > node scripts/build.js 
C:\Users\pranav\node_modules\ew\node_modules\gulp-sass\node_modules\node-sass\vendor\win32-ia32-46\binding.node exists. testing binary. Binary is fine; exiting. ew@1.1.1 C:\Users\pranav\node_modules\ew 
├── gulp-rename@1.2.2 
├── gulp-concat@2.6.0 (concat-with-sourcemaps@1.0.4, through2@0.6.5, gulp-util@3.0.7) 
├── gulp-minify-css@0.3.13 (memory-cache@0.0.5, vinyl-sourcemaps-apply@0.1.4, bufferstreams@0.0.2, through2@0.6.5, clean-css@3.0.10, gulp-util@3.0.7) 
├── gulp@3.9.1 (interpret@1.0.0, pretty-hrtime@1.0.2, deprecated@0.0.1, archy@1.0.0, minimist@1.2.0, semver@4.3.6, tildify@1.1.2, v8flags@2.0.11, chalk@1.1.1, orchestrator@0.3.7, liftoff@2.2.0, vinyl-fs@0.3.14, gulp-util@3.0.7) 
└── gulp-sass@2.2.0 (object-assign@4.0.1, vinyl-sourcemaps-apply@0.2.1, through2@2.0.1, gulp-util@3.0.7, node-sass@3.4.2)

请帮助我解决此问题。