nano-colour documentation

Documentation for the nano-colour command line tool and the NanoColour RISC OS module.

The documentation is available in the following forms:

• Modern style: the PRM layout with contemporary typefaces.
• RISC OS 3 PRM style: the familiar Programmer's Reference Manual appearance.
• RISC OS 2 PRM style: the earlier, plainer Programmer's Reference Manual appearance.
• Simple style for browsers: a plain, readable layout.
• Unstyled: no CSS, for tools and accessibility testing.