Fixed Windows compatibility for nested directories

First fix is to normalize the path slashes/backslashes. ;)

Second fix is to use comparison instead of String.match, which uses the string argument to build a regex. The regex causes problems due to backslash directory separators in Windows. The first character of any subdirectory would be treated as a special character (like \w, \s, \t, etc) by the regex constructor.

Example: /foo/bar/baz.gif
path.normalize(/foo/bar) // 'foo\\bar'
'foo\\bar'.match('foo\\bar') // null
Fixed jshint warnings
Changed equals to endsWith to include all nested paths
Restored original intent
Fixed Windows compatibility for nested directories
Merge branch 'patch-1' of github.com:cbas/grunt-usemin into patch-1
Merge pull request #62 from cbas/patch-1

Fixed Windows compatibility for nested directories