Start a document describing the new colour mechanism

Milliways Colour reference

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Description

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This document describes the text colouration options provided by Milliways

client. The legacy system refers to ANSI-16 colouring, and the updated

one to ANSI-256 support.

Legacy

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The existing colour scheme only permitted access to the 16 colour ANSI 

system and is a little awkward to use.

Each colour sequence is preceded by the Escape character, typically

entered by pressing control-V followed by the ESC key, this is followed

by two letters, the first setting the foreground colour, the second

setting the background colour, lowercase letters being the normal brightness

version, and uppercase being the brightly/intense coloured version.

* -n : Reset / Default Colour

* kK : Black

* rR : Red

* gG : Green

* bB : Blue

* cC : Cyan

* mM : Magenta

* yY : Yellow

* wW : white

ANSI 256

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For the updated colour scheme sequences are now delimited by the ampersand &

character and consist of a number of hex digits seperated by colons.

Text modes are a single hex character, colours are pairs of hex characters,

     the first colour pair being the foreground colour, the optional second

     setting the background colour.

Examples:  

* &0& - reset all attributes

* &36& - set foreground colour to purple

* &11:E3& - dark blue text on yellow background

For a full colour chart, run ~alice/ansi256.sh