UPDATE 1- UK grocery market returns to marginal growth - Kantar Worldpanel

(Refiles to fix formatting) LONDON, Dec 16 (Reuters) - Britain's grocery market eked out marginal growth of 0.1 percent in the 12 weeks to Dec. 7 after a historic first decline in last month's figures, industry data showed on Tuesday. Market researcher Kantar Worldpanel said all of Britain's so-called "big four" grocers posted sales declines in the period, while discounters Aldi and Lidl reached a record combined market share of 8.6 percent. "Britain's supermarket price war is ramp