Cascading style managers, see MetroStyleManager.cs for docs, Misc (Cycle
Global Styles) for demo.

Added MetroDefaults for general extraction of constants and default
values.

Added MetroColorStyle.Default and MetroThemeStyle.Default to prevent
designer from persisting a fixed default value.

Generate Metro<Control>Base layer to avoid code duplication.

Reworked interface hierarchy.

Fixes to Style Extender

Fixes to MetroForm / shadows

Obsoleted POINT and SIZE