Implement ASCII-only widget titles

Widget titles can now be specified in the config file via a 'title' key.
Example:

  wtf:
    mods:
      todo:
        title: Tada

which can include emoji. No need to force everyone to look at my emoji,
now they can define their own.

newrelic/widget.go

@@ -39,7 +39,7 @@ func (widget *Widget) Refresh() {
 	}
 
 	widget.UpdateRefreshedAt()
-	widget.View.SetTitle(fmt.Sprintf(" New Relic: [green]%s[white] ", appName))
+	widget.View.SetTitle(fmt.Sprintf("%s- [green]%s[white]", widget.Name, appName))
 	widget.View.Clear()
 
 	if depErr != nil {