Update file URL simplification code

Earlier fix for local file access on webOS 3 devices disabled
use of local file access when fetching a page from a Windows file
share. This makes that omitting of the hostname conditional on
it being a webOS 3 or earlier device.

Enyo-DCO-1.1-Signed-Off-By: Ben Combee (ben.combee@lge.com)
Merge pull request #543 from enyojs/fix-file-access

Update file URL simplification code