effectively resolves#1200
* Replaced floats in FloatRange with ints (would have used shorts but
SubGBHawk/SubNesHawk use an axis to hack in cycle count or something), added
both Range<int> and Range<float> auto-properties
* Added bool field IsReversed to FloatRange
* Added enum AxisPairOrientation and factory method using it
* Cleaned up usages of FloatRange fields and properties
* Added new properties to PadSchema.ButtonSchema for type
PadInputType.AnalogStick (to hold the two FloatRanges) and used
ControllerDefinitions from cores to dedup these ranges in the schemata
* Made VirtualPadAnalogStick work properly: both the direction and bounds are
correctly set from the controller schemata, the polar conversion measures angles
consistently (though I think it might not work outside -128..127 e.g. for PSX),
and I didn't break the sensitivity override, plus negative percentages might
work now but I didn't allow those
* Renamed FloatRange to AxisRange, but did not rename related symbols
* Use expression bodies in Emulation.Cores, and a few other misc cleanups
* remove unused usings in Emulation.Common
* cleanups in Tables_Direct.cs
* some cleanups in nes boards - redundant code
* remove some redundant array initializers in Emulation.Cores
* cleanup AmstradCPC.Controllers
* use object initializers in a lot of places
* nes mappers - remove disch's notes comments in favor of the nesdev wiki link
* cleanup CdtConverter.cs, mostly use of object initializers
* remove redundant .ToString() calls in Emulation.Cores
* using var in Emulation.Cores
* AmstradCPC/ZXSpectrum - simplify some linq, tabs instead of spaces, a few other misc cleanups
* Use null-propagation in Emulation.Cores
* Rewind & State config - remove the default option
* remove the savestate type of default, not that this is a breaking config change for anyone that had specifically set savestates to text
* remove BinaryStatesPreferred from IStatable and use config setting when starting movies from "Now" in record movie dialog
* remove BinaryStatesPreferred from cores
* make text savestates an extension method off of IStatable and an inteface ITextStatable it uses if the core implements it. This will allow cores to opt in to text states if desired
* make cores with actual text savestate impleemntations get ITextStatable, remove text state logic from cores that just have a binary as as text implementation