By Lars Hagberg and Kyaw Soe Oo OTTAWA (Reuters) -Canadian police on Sunday smashed the windows of vehicles abandoned in the downtown core of the capital to tow them away, and city workers cleaned up trash after two days of tense standoffs and 170 arrests ended a three-week occupation of Ottawa. Demonstrators had used hundreds of trucks and vehicles to block the city since Jan. 28, prompting Prime Minister Justin Trudeau to invoke rarely used emergency powers. There were a few stragglers on Sunday packing up a logistics depot the so-called “Freedom Convoy” had set up in a parking lot near the …