fixing unescaped character in date function

Conflicts:
	includes/shortcodes/class-wc-shortcode-my-account.php
	templates/order/tracking.php
Tweaked popularity sorting to work better when no sales are present.

Conflicts:
	readme.txt
Merge remote-tracking branch 'woo/release-2-0-15' into release-2-0-15-tivnet