DALLAS, Jan 19 (Reuters) - Country music singer Randy Travis has reached a plea agreement in a misdemeanor assault case arising from an altercation last summer in a Texas church parking lot, KTVT-TV reported on Saturday. The Grammy winner will serve 90 days of deferred adjudication under a plea he entered on Friday in a municipal court in Plano, a Dallas suburb, the CBS-affiliated station in Dallas/Forth Worth reported.