location sharing: minor fonts changes

- text label font-sixe from 20 to 15
- text label length from 10 to 20

Change-Id: Ibcfc6f3dee298aaa614dc3bd0b0ce653c88496ac

src/app/positionmanager.cpp

@@ -486,7 +486,7 @@ PositionManager::addPositionToMap(PositionKey key, QVariantMap position)
         bestName = accountInfo.contactModel->bestNameForContact(uri);
 
     QString shorterAuthorName = bestName;
-    shorterAuthorName.truncate(10);
+    shorterAuthorName.truncate(20);
     if (bestName != shorterAuthorName) {
         shorterAuthorName = shorterAuthorName + "…";
     }

src/app/webengine/map/map.js

@@ -97,7 +97,7 @@ function setSource (coordos, avatar, authorName) {
     textLabel.setStyle(new ol.style.Style({
       text: new ol.style.Text({
         text: textLabel.get('text'),
-        font: '20px Arial',
+        font: '15px Arial',
         fill: new ol.style.Fill({
           color: 'black'
         }),