[chronojump] Fixed bug on no person at compujump at run interval

[Xavier de Blas <xaviblas src gnome org>]

commit 90075d84b4a524ae41c637650af136d313b02744
Author: Xavier de Blas <xaviblas gmail com>
Date:   Sun Jul 9 19:34:03 2017 +0200

    Fixed bug on no person at compujump at run interval

 src/gui/chronojump.cs |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/gui/chronojump.cs b/src/gui/chronojump.cs
index 9d44d16..e23203d 100644
--- a/src/gui/chronojump.cs
+++ b/src/gui/chronojump.cs
@@ -991,7 +991,8 @@ public partial class ChronoJumpWindow
                else if(radio_menuitem_mode_runs_intervallic.Active)
                {
                        updateGraphRunsInterval();
-                       label_sprint_person_name.Text = string.Format(Catalog.GetString("Sprints of {0}"), 
currentPerson.Name);
+                       if(currentPerson != null)
+                               label_sprint_person_name.Text = string.Format(Catalog.GetString("Sprints of 
{0}"), currentPerson.Name);
                        createTreeView_runs_interval_sprint (treeview_runs_interval_sprint);
                }
                else if(radio_menuitem_mode_rt.Active)