* 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
alyosha-tas