AOL said today it has launched 100 Patch local news sites and has plans to grow that number to 500 by the end of the year. AOL plans to hire 500 journalists to support its Patch expansion and it will likely be the largest hirer of full-time journalists in the U.S. this year. "Today's launch of our 100th site is a significant milestone for us. We began with just three Patch communities in February 2009,