FALL RIVER — An anonymous donor has pledged a $2,000 reward for information leading to the conviction of the person who shot a local woman’s cat with a BB gun last month, mortally injuring the pet, police said Thursday. The donor, described by a police spokesman as a generous supporter of the Rhode Island SPCA who wishes to remain anonymous, pledged the funds after learning of the death of a pet cat named Wolf. “Despite the incident being outside of the Rhode Island