COLIN MACINNES (1914-76), son of novelist Angela Thirkell, cousin of Stanley Baldwin and Rudyard Kipling, grandson of Burne-Jones, was brought up in Australia but lived most of his life in London about which he wrote with a warts-and-all relish that earned him a reputation as the literary Hogarth of his day. Bisexual, outsider, champion of youth, pale-pink friend of Black Londoners and chronicler of English life, MacInnes described himself as a very nosy person who found adultery in Hampstead indescribably dull and was much more at home in the coffee bars and jazz clubs of Soho and Notting Hil