Bug with Envjs.WriteToFile in envjs/platform/rubyracer.js on Linux

[falaise]

Hi,

if you run './bin/envjs rubyracer ./examples/pictures/boot.js'
you receive an exception because Envjs.WriteToFile fails to open the file to write.
Just add in the source of WriteToFile this test :
if(/^file:///.test(url))
url = url.substring(7,url.length);

Regards.