Added YLabel splitter and Extra info on tooltip

Actually, custom label are not allowed, it directly uses the provided by
the query result as the target/alias

This feature allows to:

- Split YLabel to store its partials and reuse them on link and extra tooltip field
- Override YLabel with splitted and custom values
- Added Extra Tooltip to show metadata to the user on each serie

dist/statusmap_data.js

@@ -48,6 +48,8 @@ System.register([], function (_export, _context) {
 
           _defineProperty(this, "yLabel", "");
 
+          _defineProperty(this, "pLabels", []);
+
           _defineProperty(this, "x", 0);
 
           _defineProperty(this, "xid", 0);
@@ -117,6 +119,8 @@ System.register([], function (_export, _context) {
 
           _defineProperty(this, "targets", []);
 
+          _defineProperty(this, "pLabels", {});
+
           _defineProperty(this, "rangeMs", 0);
 
           _defineProperty(this, "intervalMs", 0);