Merge pull request #6 from hansott/patch-1

Fix typo in option description

Author: lahmatiy

index.js

@@ -190,7 +190,7 @@ var command = cli.create('csso', '[input] [output]')
     .option('-i, --input <filename>', 'Input file')
     .option('-o, --output <filename>', 'Output file (result outputs to stdout if not set)')
     .option('-m, --map <destination>', 'Generate source map: none (default), inline, file or <filename>', 'none')
-    .option('-u, --usage <filenane>', 'Usage data file')
+    .option('-u, --usage <filename>', 'Usage data file')
     .option('--input-map <source>', 'Input source map: none, auto (default) or <filename>', 'auto')
     .option('--restructure-off', 'Turns structure minimization off')
     .option('--comments <value>', 'Comments to keep: exclamation (default), first-exclamation or none', 'exclamation')