LONDON (Reuters) - European shares rallied and the euro took a sharp hit on Tuesday in a knee-jerk reaction to European Central Bank President Mario Draghi's comments indicating a possibility of new rate cuts or asset purchases.The euro fell 0.24% to 1.1191 as of 0845 GMT after Draghi said the ECB will need to ease policy again, if inflation doesn't head back to its targets, and that there was still "considerable headroom" to do it.Those signals come a day ahead of the widely anticipated U.S...