Remove unused import from DialectMySQL

Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/src/main/java/com/google/gwtorm/schema/sql/DialectMySQL.java b/src/main/java/com/google/gwtorm/schema/sql/DialectMySQL.java
index 0844e4c..043b3ad 100644
--- a/src/main/java/com/google/gwtorm/schema/sql/DialectMySQL.java
+++ b/src/main/java/com/google/gwtorm/schema/sql/DialectMySQL.java
@@ -18,7 +18,6 @@
 import com.google.gwtorm.client.OrmException;
 import com.google.gwtorm.client.Sequence;
 import com.google.gwtorm.schema.ColumnModel;
-import com.google.gwtorm.schema.RelationModel;
 import com.google.gwtorm.schema.SequenceModel;
 
 import java.sql.Connection;