UK Stocks-Factors to watch on May 23

May 23 (Reuters) - Britain's FTSE 100 index is seen opening 19 points lower at 7,858 on Wednesday, according to CMC Markets. * BANK OF ENGLAND: Bank of England Governor Mark Carney said on Tuesday he expected Britain's economy would bounce back from a weak start to the year when it was hit by heavy snowstorms, keeping the prospect of higher interest rates on the table. * SHELL: Top investors in Royal Dutch Shell on Tuesday put pressure on the oil and gas giant to commit to hard