Add new previews for the Transformations section

Author: thkwznk

canvas.md

@@ -25,6 +25,4 @@ You can change the canvas size using the current selection bounds:
 You can remove transparent borders automatically from the canvas 
 using the *Sprite > Trim* menu.
 
-<!-- PREVIEW: GIF, trim canvas with a sprite miming being enclosed in a box -->
-
-![Trim Preview](canvas/trim.gif)
+![Trim Preview](canvas\canvas-trim.gif)

canvas/canvas-flip.gif

@@ -9,3 +9,5 @@ To flip the canvas horizontally, you can select *Sprite > Rotate Canvas > Flip C
 ## Flip Canvas Vertical
 
 To flip the canvas vertically, you can select *Sprite > Rotate Canvas > Flip Canvas Vertical* menu.
+
+![Flip Canvas Preview](canvas/canvas-flip.gif)

canvas/canvas-rotate.gif

@@ -1,13 +1,11 @@
 # Flip Sprite or Selection
 
-<!-- PREVIEW: GIF, flipping a sprite, then a selection -->
-
-![Flip preview](flip/flip.gif)
-
 ## Flip Horizontal
 
 To flip the sprite or selection horizontally, you can select *Edit > Flip Horizontal* menu (<kbd>Shift+H</kbd>).
 
 ## Flip Vertical
 
 To flip the sprite or selection vertically, you can select *Edit > Flip Vertical* menu (<kbd>Shift+V</kbd>).
+
+![Flip preview](flip/flip.gif)

canvas/canvas-trim.gif

@@ -10,4 +10,4 @@ You can resize your sprite using *Edit > Sprite Size* menu option.
 
 You can resize a selection using handles.
 
-<!-- PREVIEW: GIF, resize a selection using handles -->
+![Resize selection using handles](resize/resize-selection.gif)