Major refactoring of octoprint.server.util (divided into smaller submodules), extended Tornado to allow for request-specific max content lengths, introduced settings parameters to configure maximum upload size, maximum request body size and file suffixes
See #455
Changed some endpoints again (removed "/control" path element) and made API spit out only raw data (e.g. seconds, millimeters, unix timestamps etc) instead of formatted versions. Modified frontend to take care of formatting this data itself.
