ColorEcho - adding colour to echoed batch text

We use batch files for... well, pretty much everything. From simple files that simple optimize modified graphics, to the tendril-like files that build our software. For some time now, I've been using `cecho.exe` from a CodeProject article so that I highlight errors and successes. Sadly this tool doesn't output anything if a console window isn't in use (for example from a CI server) and so I created a quick C# version for a direct replacement.

Richard Moss