Hi,

the JSON parser handles backslash escapes improperly. Example:

    local data = [[ { "escapes" : "(\")(\\)(\b)(\f)(\n)(\r)(\t)",
                      "invalid" : "\'\v" } ]]
    local stuff = utilities.json.tolua (data)
    inspect(stuff)

Currently it chokes on double quotes and treats the other escapes
like Lua. Fix suggestion attached.

Best regards,
Philipp