GLOBAL MARKETS-Shares, oil and rouble rally into Christmas period

* European bourses open higher helped by Greek political hopes * Euro bounces back, rouble rallies as oil jumps above $62 * Emerging markets, CAD and AUD make ground By Marc Jones LONDON, Dec 22 (Reuters) - World share markets extended their 'Santa rally' into a fourth day on Monday, as a recovery in beaten-down oil prices and the rouble and more calls for quantitative easing from the ECB helped lift sentiment. There were also hopes that Greece could avoid destabilising snap