By Carolyn Cohn LONDON (Reuters) – World stocks rose in holiday-thinned trade on Monday, helped by a bounce in oil as concerns over tight supply outweighed recession fears. European stocks rallied 0.8% and Britain’s FTSE rose over 1%, boosted by gains in oil and gas companies. [.EU][.L] Oil dropped $1 a barrel earlier on Monday on worries about the global economic outlook, but roared back on data showing lower output from the Organization of the Petroleum Exporting Countries (OPEC), and on unrest in Libya and sanctions on Russia. Ecuador’s oil production has been hit by unrest recently, and a …