Use type tuple() instead of record()

Dialyzer doesn't recognize the type `record()`, and gives this error message:

    dialyzer: Analysis failed with error:
    Could not scan the following file(s): [{"/home/magnus/src/LINC-Switch/deps/enetconf/src/gen_netconf.erl",
                                            "  Error while parsing #edit_config{}: Unable to find type record\n\n"},
                                           {"/home/magnus/src/LINC-Switch/deps/enetconf/src/enetconf_xml.erl",
                                            "  Error while parsing #edit_config{}: Unable to find type record\n\n"},
                                           {"/home/magnus/src/LINC-Switch/deps/enetconf/src/enetconf_ssh.erl",
                                            "  Error while parsing #edit_config{}: Unable to find type record\n\n"},
                                           {"/home/magnus/src/LINC-Switch/deps/enetconf/src/enetconf_parser.erl",
                                            "  Error while parsing #edit_config{}: Unable to find type record\n\n"},
                                           {"/home/magnus/src/LINC-Switch/deps/enetconf/src/enetconf_client.erl",
                                            "  Error while parsing #edit_config{}: Unable to find type record\n\n"},
                                           {"/home/magnus/src/LINC-Switch/deps/enetconf/src/enetconf_capabilities.erl",
                                            "  Error while parsing #edit_config{}: Unable to find type record\n\n"}]

With `tuple()`, Dialyzer is able to analyse the code.