escaping the windows file.seperator for the regex (fix for #14)

[neomaclin]

Tested with the test case provided(on Windows 7).

[huntc]

Hi @neomaclin,

Thank you for your contribution. Would you mind signing our CLA?

http://www.typesafe.com/contribute/cla

Thanks!

[huntc]

Thanks for this. Could I also get you to squash your commits?

[neomaclin]

Hi Chris. No problem, Done and Done

[huntc]

Thanks!

[DGolubets]

Hi! This fix is not correct.
File separator in Windows is backslash. Thus generated regex fails to match paths from main.js cos they are defined in URL format with slashes.
It should be

private def withEscapedSep(p: String): String = withSep(p).replace("\\","/")

P.S. This may not be enough, I see generated paths like "lib\bootstrap/js/bootstrap" in app.build.js which looks wrong..

[huntc]

The important thing here is that we correctly distinguish between a file path and a uri path and treat the sep properly. It seems to me that we may have them confused in places.