Merge pull request #7 from rsaxvc/master

Expand viewing area, smaller tiles
Try to limit queue lengths
Fix excessive memory usage on zoom

* Pull up imageresampler
* Reduce copies/allocations in GetScaledSubrect()
* Bump VS2012 warning level from 3 to 4
Fix "fit image to window"
Improve tile generation order

Resort the tile queue on redraw so that tiles closer to the center of
the current viewport are generated first.
Switch to stb_image_resize.h for resampling

* Remove imageresampler in favor of stb_image_resize.h
* Remove LinearImage and use wxImages directly
Enable key repeat for zoom in/out
Consume stb_image_resize.h as a submodule
Move source files to src directory
gitignore Visual Studio Performance Report (.vsp) files
Update README.md
Complete qanddview -> qndview rename
Reduce flicker

Reduce flicker by only erasing the parts of the window that won't be
overwritten by the image.
Clean up public ScaledImageFactory types
Add support for animation loading/playback
Don't update LRU info in QueueRect()
Roll SetScale() into SetImage()
Add disabled code for nearest-neighbor filtering
Fix copy/paste bug
Don't resort queued rects from OnThread()