Feature/langloc

This will return a client.json file based on user preference.
It will work from most preferred to least, to "en" as the default.
It also presumes all pathnames are in lower case (because LCD)

@kitcambridge, @nchapman r?
space should already be trimmed out by the strings.Map above. (in fact, just realized that I can drop the space from strings.TrimLeft() )