FIJITestsViewer: add keyboard accelerators for update, start, stop

bin/Tk/FIJITestsViewer.pm

@@ -441,21 +441,33 @@ sub _populate_widget {
             -side => "bottom",
             -fill => 'both',
         );
+
         $self->{'update_button'} = $self->{'fr_buttons'}->Button(
             -text    => "Update",
             -command => [\&_update_fiji_status, $self],
-            -state   => (defined $self->{'Downloader'}) ? "normal" : "disabled"
+            -state   => (defined $self->{'Downloader'}) ? "normal" : "disabled",
+            -underline => 0,
         );
+        $self->MainWindow->bind("<Alt-u>" => [ $self->{'update_button'}, 'Invoke']);
+        $self->MainWindow->bind("<F5>" => [ $self->{'update_button'}, 'Invoke']);
+
         $self->{'start_button'} = $self->{'fr_buttons'}->Button(
             -text    => "Start",
             -command => [\&_start_test, $self],
-            -state   => (defined $self->{'Downloader'}) ? "normal" : "disabled"
+            -state   => (defined $self->{'Downloader'}) ? "normal" : "disabled",
+            -underline => 0,
         );
+        $self->MainWindow->bind("<Alt-s>" => [ $self->{'start_button'}, 'Invoke']);
+        $self->MainWindow->bind("<F6>" => [ $self->{'start_button'}, 'Invoke']);
+
         $self->{'stop_button'} = $self->{'fr_buttons'}->Button(
             -text    => "Stop",
             -command => [\&_stop_test, $self],
-            -state   => "disabled"
+            -state   => "disabled",
+            -underline => 3,
         );
+        $self->MainWindow->bind("<Alt-p>" => [ $self->{'stop_button'}, 'Invoke']);
+        $self->MainWindow->bind("<F7>" => [ $self->{'stop_button'}, 'Invoke']);
 
         $self->{'stop_button'}->pack(-side => "right");
         $self->{'start_button'}->pack(-side => "right");