Version 6.2.1

* Tweak generic timing to be more stable by using a division-based H-Freq

Version 6.2

* More realistic RF simulation

* Add specialized Mega Drive presets

* Add PC Engine presets

* Filter parameter values were tweaked and tap counts optimized for accuracy

* Framing was resized to optimize performance; oversampling applied by composite shader pipelines as needed

* A compiling issue with certain Mega Drive/Genesis presets on Vulkan was fixed

Version 6.1.1

* Add generic presets, based on standard timing; may not be accurate.

* Add Mega Drive presets

* Add Neo Geo presets

* Enable different output aspect ratios besides 16:9; smartly letterboxes and crops for ideal presentation

* Add arcade bezels: flat is a rectangular border, tvstyle is in the shape of a 'bubble' tv viewport

* Remove glow jitter parameter

Version 6.1

* Allow for color keyed JPEGs to be used for bezel

Version 6.0

* Completely new shader system, first version included with RetroArch

Version 4.2

* Adds more presets, mostly for monochrome monitors.

Version 4.1

* Fixes a bug with line doubler.

* Adds Scanline Basic preset

* Adjusts focus on various presets.

Version 4.0

* Adds support for multi-scan.  The following parameters have been
  added: SCAN_TYPE, MAX_SCAN_RATE, LINE_DOUBLER, INT_OFF

* The following parameters have been removed: ON_PIXELS, OFF_PIXELS,
  HI_RES_THRES

Version 3.1

* Fixes a bug with color transformations.

Version 3.0

* New phosphor decay model (requires 3-pass setup).

Version 2.0

* Added support for shadow masks provided by hunterk.

* Changed gamma model to simple 2.4 power law.
