Add optional prettyStatusMessage to Job.

src/libcalamares/Job.cpp

@@ -94,4 +94,11 @@ Job::prettyDescription() const
 }
 
 
+QString
+Job::prettyStatusMessage() const
+{
+    return QString();
+}
+
+
 } // namespace Calamares

src/libcalamares/Job.h

@@ -65,6 +65,7 @@ public:
 
     virtual QString prettyName() const = 0;
     virtual QString prettyDescription() const;
+    virtual QString prettyStatusMessage() const;
     virtual JobResult exec() = 0;
 signals:
     void progress( qreal percent );