refactored RGBImage

Refactored RGBImage to use a templated base class. This will allow future expansion
to other matrix types, such as  bi-color LEDs or gray-scale monochrome LEDs.

Author: michaelkamprath

CHANGELOG.md

@@ -0,0 +1,18 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+###Changed
+* Refactored the image classes to have a common, templated base class. This consolidates similar logic to a single location.
+
+
+## [1.0.1] - 2017-12-24
+### Fixed
+* Corrected failure to compile for boards that can only use 6-bit color.
+
+## [1.0.0] - 2017-12-24
+Initial release