By Matt Tracy, Nivedita Balu and Davide Barbuscia (Reuters) -Global companies including Citigroup and McDonald's have flocked to Canada's bond market this year, drawn by strong investor appetite and cheaper borrowing costs, according to LSEG data, analysts and investors. The trend also reflects a growing willingness among issuers and investors to shift away from the dollar as uncertainty created by U.S. President Trump's trade policies lingers. Issuance of "Maple bonds" by foreign borrowers in the Can ...