Dollar Tree has saved 170 shops that were set to be shuttered by rival 99 Cents Only after it went bankrupt.It is a boost for budget shoppers in Arizona, California, Nevada, and Texas - who have been mourning the loss of the popular chain.Dollar Tree announced on Wednesday that it had bought rights to the leases for the stores.At the same time, it has paid for the 99 Cents Only's 'intellectual property,' meaning it has the option to keep some stores open under the brand or even open new ones using it.West Coast-based 99 Cents Only had a cult following...