Use document.createStyleSheet when is possible.

There is a known bug in IE when create <link> tag on the fly. Use document.createStyleSheet when is possible.

More info: http://msdn.microsoft.com/en-us/library/ie/ms531194(v=vs.85).aspx
Merge pull request #9 from dosten/patch-1

Use document.createStyleSheet when is possible.
Merge branch 'json-stringify-escape'
Support for manual injection. Usage: -t [cssify --no-auto-inject]
Support for adding styles into an iframe
0.5.0