By Michael Holden LONDON (Reuters) – Queen Elizabeth marks 70 years on the British throne on Sunday, a milestone never reached by any of her predecessors over the last 1,000 years, and one which only a few monarchs across the globe have ever achieved. Elizabeth, 95, became the queen of Britain and more than a dozen other realms including Canada, Australia and New Zealand on the death of her father King George VI on Feb. 6, 1952, while she was in Kenya on an international tour. The news was broken to her by her husband Prince Philip, who died last year aged 99 after more than seven decades by h…