Failing on windows with Node.js > v.0.12.x

I guess you are more the expert for npm than me :D

```
> optional-dev-dependency hiredis

npm WARN invalid config access=undefined
npm WARN invalid config https-proxy=undefined
npm WARN invalid config Must be a full url with 'http://'
npm WARN invalid config init-author-url=undefined
npm WARN invalid config Must be a full url with 'http://'
npm WARN invalid config proxy=undefined
npm WARN invalid config Must be a full url with 'http://'
npm ERR! Windows_NT 6.3.9600
npm ERR! argv "C:\\Program Files (x86)\\iojs\\node.exe" "C:\\Program Files (x86)\\iojs\\node_modules\\npm\\bin\\npm-cli.js" "install" "hiredis"
npm ERR! node v3.0.0
npm ERR! npm v2.13.3
npm ERR! code MODULE_NOT_FOUND

npm ERR! Cannot find module 'undefined'
npm ERR!
npm ERR! If you need help, you may report this error at:
npm ERR!
npm ERR! Windows_NT 6.3.9600
npm ERR! argv "C:\\Program Files (x86)\\iojs\\node.exe" "C:\\Program Files (x86)\\iojs\\node_modules\\npm\\bin\\npm-cli.js" "install" "hiredis"
npm ERR! node v3.0.0
npm ERR! npm v2.13.3

npm ERR! error:0906D06C:PEM routines:PEM_read_bio:no start line
npm ERR!
npm ERR! If you need help, you may report this error at:
npm ERR!

npm ERR! Please include the following file with any support request:
npm ERR! C:\projects\node-redis\npm-debug.log
```