Add useGetBytesForBlob option in camel-jdbc

As described in Oracle documentation(avaliable at http://docs.oracle.com/cd/E18283_01/java.112/e16548/oralob.htm#CHDCDFAC ): "The getString and getNString methods cannot be used for retrieving BLOB column values". So i changed the component to accept an option to use the getBytes method instead.