JAVA-837: Allow use of "text" command on non-primaries by adding it the list of commands that obey the requested read preference.

Author: jyemin

src/main/com/mongodb/DB.java

@@ -50,6 +50,7 @@ public abstract class DB {
         _obedientCommands.add("geonear");
         _obedientCommands.add("geosearch");
         _obedientCommands.add("geowalk");
+        _obedientCommands.add("text");
     }
 
     /**

src/test/com/mongodb/DBTest.java

@@ -122,6 +122,9 @@ public void testReadPreferenceObedience() {
 
         obj = new BasicDBObject("collStats", 1);
         assertEquals(ReadPreference.secondaryPreferred(), _db.getCommandReadPreference(obj, ReadPreference.secondaryPreferred()));
+
+        obj = new BasicDBObject("text", 1);
+        assertEquals(ReadPreference.secondaryPreferred(), _db.getCommandReadPreference(obj, ReadPreference.secondaryPreferred()));
     }
 
     @Test(groups = {"basic"})