The Astros announced Thursday 18 non-roster spring training invitations, including second baseman Delino DeShields, center fielder George Springer and outfielder Rick Ankiel. Ankiel agreed to a contract Thursday with the Astros, which includes a spring training invite. Houston’s major-league roster is at the maximum of 40. Fifty-eight players (28 pitchers, 30 position) will enter camp. Pitchers and catchers report Feb. 11 in Kissimmee, Fla., while position players arrive Feb. 15. First baseman Jonathan Singleton, who recently failed a minor-league drug test and is suspended for the initial 50 games of 2013, was not invited to the Astros’ spring training. Press release: Both DeShields, 20, and Springer, 23, had outstanding minor [...]