Icons tweaked #4469

- The "light" icon theme is now a little lighter, to increase contrast.
- Toolbox icons are now small.
- Buttons:
  - Buttons without labels which use icons as their only source of info regarding what the button does (e.g. the white-balance pipette button) use normal-sized icons.
  - Labeled buttons which use icons as an auxiliary source of information (e.g. Auto-Crop) now use small icons. Curve type icons are also small even though they have no labels.
- Colored circles are smaller.
- Curve type icons redesigned and small.
- Hand icons (when panning the preview) redesigned to have a clear outline regardless of background color.
- Magnifier icons redesigned to have a thinner magnifier frame and larger inner parts.
- Perspective, distortion and crop icons redesigned.
- Some small icons were missing the `-small` suffix, now renamed.

rtgui/rotate.cc

@@ -30,15 +30,15 @@ Rotate::Rotate () : FoldableToolPanel(this, "rotate", M("TP_ROTATE_LABEL"))
     rlistener = nullptr;
 
     //TODO the action of the rotation slider is counter-intuitive
-    Gtk::Image* irotateL =   Gtk::manage (new RTImage ("rotate-right.png"));
-    Gtk::Image* irotateR =   Gtk::manage (new RTImage ("rotate-left.png"));
+    Gtk::Image* irotateL =   Gtk::manage (new RTImage ("rotate-right-small.png"));
+    Gtk::Image* irotateR =   Gtk::manage (new RTImage ("rotate-left-small.png"));
 
     degree = Gtk::manage (new Adjuster (M("TP_ROTATE_DEGREE"), -45, 45, 0.01, 0, irotateL, irotateR));
     degree->setAdjusterListener (this);
     pack_start (*degree);
 
     selectStraight = Gtk::manage (new Gtk::Button (M("TP_ROTATE_SELECTLINE")));
-    selectStraight->set_image (*Gtk::manage (new RTImage ("rotate-straighten.png")));
+    selectStraight->set_image (*Gtk::manage (new RTImage ("rotate-straighten-small.png")));
     pack_start (*selectStraight, Gtk::PACK_SHRINK, 2);
 
     selectStraight->signal_pressed().connect( sigc::mem_fun(*this, &Rotate::selectStraightPressed) );