Correct install instructions for grunt 0.3x 

The indicated version grunt-css@0.4.1 would give me a TypeError, with tag 0.3.2 it works, just got an npm error while installing :

npm WARN package.json csslint@0.9.9 No README.md file found!



TypeError: Object #<Object> has no method 'options'
    at Object.module.exports (/htdocs/node_modules/grunt-css/tasks/grunt-css.js:74:24)
    at Object.task.registerMultiTask.thisTask (/htdocs/node_modules/grunt/lib/grunt/task.js:109:15)
    at Object.task.registerTask.thisTask.fn (/htdocs/node_modules/grunt/lib/grunt/task.js:58:16)
    at Task.<anonymous> (/htdocs/node_modules/grunt/lib/util/task.js:343:36)
    at Task.<anonymous> (/htdocs/node_modules/grunt/lib/util/task.js:319:9)
    at Task.<anonymous> (/htdocs/node_modules/grunt/lib/util/task.js:346:11)
    at Task.start (/htdocs/node_modules/grunt/lib/util/task.js:359:5)
    at Object.grunt.tasks (/htdocs/node_modules/grunt/lib/grunt.js:143:8)
    at Object.module.exports [as cli] (/htdocs/node_modules/grunt/lib/grunt/cli.js:36:9)
    at Object.<anonymous> (/usr/local/lib/node_modules/grunt/bin/grunt:19:14)