bump support for libreview 4.7.0

See timoschlueter/nightscout-librelink-up#101 for more
information.

lib/sources/librelinkup.js

@@ -1,6 +1,7 @@
 
 var qs = require('qs');
 var url = require('url');
+
 const _LluApiEndpoints = {
     AE: "api-ae.libreview.io",
     AP: "api-ap.libreview.io",
@@ -19,10 +20,12 @@ var Defaults = {
   Connections: '/llu/connections',
   Graph: '/llu/connections/',
   mime: 'application/json',
-  Version: '4.2.2',
+  Version: '4.7.0',
   Product: 'llu.ios',
 
 };
+var software = require('../../package.json');
+var user_agent_string = [software.name, `${software.name}@${software.version}`, `LibreView@${Defaults.Version}`, software.homepage].join(', ');
 
 function mapArrowTrend (trend) {
   return mapArrowTrend.map[trend] || mapArrowTrend.map.default;
@@ -49,6 +52,7 @@ function linkUpSource (opts, axios) {
                           'Accept': Defaults.mime,
                           'Accept-Encoding': "gzip, deflate, br",
                           'version': opts.linkUpVersion,
+                          'User-Agent': user_agent_string,
                           'product': opts.linkUpProduct
                         };
   var baseURL = opts.baseURL;