made moving in the project model undoable

app/ui/style/css/olive-dark.css

@@ -28,6 +28,7 @@
 
   Main:            #353535
   Text:            #ffffff
+  Disabled Text:   #808080
   Highlights:      #2a82da
   Highlight Text:  #ffffff
   Dark:            #191919
@@ -46,6 +47,11 @@ QWidget::selected {
   color: #ffffff;
 }
 
+/* Default disabled colors */
+QWidget::disabled {
+  color: #808080;
+}
+
 /* Default link color */
 a {
   color: #2a82da;

app/ui/style/css/olive-light.css

@@ -28,6 +28,7 @@
 
   Main:            #d0d0d0
   Text:            #000000
+  Disabled Text:   #808080
   Highlights:      #2a82da
   Highlight Text:  #ffffff
   Dark:            #f0f0f0
@@ -46,6 +47,11 @@ QWidget::selected {
   color: #ffffff;
 }
 
+/* Default disabled colors */
+QWidget::disabled {
+  color: #808080;
+}
+
 /* Default link color */
 a {
   color: #2a82da;

app/ui/style/css/olive-mid.css

@@ -28,6 +28,7 @@
 
   Main:            #808080
   Text:            #000000
+  Disabled Text:   #808080
   Highlights:      #2a82da
   Highlight Text:  #ffffff
   Dark:            #c0c0c0
@@ -46,6 +47,11 @@ QWidget::selected {
   color: #ffffff;
 }
 
+/* Default disabled colors */
+QWidget::disabled {
+  color: #808080;
+}
+
 /* Default link color */
 a {
   color: #2a82da;