Add scaleMode to FastImageItem
Initial implementation of FolderLayout
Use a list of items instead of QML children with FolderLayout
Allow clicking on FolderLayout items
Use delayed layout in FolderLayout to handle multiple invalidations

This saves some extra layout cycles when many changes happen at
once, as often happens during initial load or in some cases with
the image cache.
Use a single instance of FolderLayout instead of re-using a Loader

This is faster, and avoids some bugs caused by the Loader.
Disable fade-in on FolderLayout images that are immediately available

Images that are already loaded in the cache can be displayed instantly
with no need for a fade-in; this provides a much better experience
when switching out of a folder.
Trigger a layout immediately after setup in FolderLayout

This is done to avoid a flicker caused by the 1ms delay for scheduled
layouts.
Display the first file for subfolders in FolderLayout

This provides a better content overview for folders containing
other folders.
Improve FolderLayout appearance with same-sized images

When all rows have the same height, and the last row is incomplete,
it looks better to keep that height. This is especially noticable
for folders with images of exactly the same size.
Show a light position indicator on the filmstrip for context
Put a shadow line between filmstrips for a sense of separation
Add FastImageItem paintedHeight and paintedWidth properties
Make the filmstrip vertical padding slightly smaller

Unfortunately, I can't yet find a way to make this even.
Remove the animation for the current item of a Filmstrip

This feels much better when it instantly moves to the next item,
and fixes some scrolling edge cases. The current item is also
more exactly centered now.
Always put the current item in a filmstrip in the center of the window

This is an experimental UI change, may be reverted.
Change the filmstrip highlight item dramatically

Experimental, as always
Hide the mouse in fullscreen mode when still
Simple swipe gestures for up/down/left/right

This currently assumes OS X Lion-like behavior, where moving your
fingers right swipes left.
Fix clicking with PinchArea