DATAMONGO-1421 - Polishing.

Remove trailing whitespaces. Construct exception message with String.format(…).

Original pull request: #448.

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/query/Query.java

@@ -95,8 +95,8 @@ public class Query {
 			this.criteria.put(key, criteriaDefinition);
 		} else {
 			throw new InvalidMongoDbApiUsageException(
-					"Due to limitations of the com.mongodb.BasicDBObject, " + "you can't add a second '" + key + "' criteria. "
+					String.format("Due to limitations of the com.mongodb.BasicDBObject, you can't add a second '%s' criteria. "
-							+ "Query already contains '" + serializeToJsonSafely(existing.getCriteriaObject()) + "'.");
+							+ "Query already contains '%s'", key, serializeToJsonSafely(existing.getCriteriaObject())));
 		}
 
 		return this;