path separator on windows in handlebar templates with libraries

When referring a library that is in the parent directory, the ..\ path is appended to the handlebar templates name (on windows).

The check for the template.root doesn't work on windows, when templates/ is used, because windows uses \ as separator.
-> A global guideline for using path separator should be defined. I would suggest, that only / are used and path.normalize is called when we access the file or directory on the filesystem