CANADA STOCKS-TSX flat in light trading; TransCanada, gold miners drop

* TSX closes down 6.71 points, or 0.05 percent, at 14,493.68 * TransCanada off 3.7 percent on Keystone XL pipeline delay * Gold miners drop as Barrick-Newmont merger talks hit snag By Solarina Ho TORONTO, April 21 (Reuters) - Canada's main stock index was little changed in thin Easter holiday trading on Monday with drops in Barrick Gold Corp and TransCanada Corp , which was hit by another delay for its Keystone XL pipeline project, offsetting gains in other groups. Markets i