DB comment size has been increased since MySQL-5.5.3 so increase it

Increase the DB comment size of MySQL in DDL creation process.

 DB comment size has been increased since MySQL-5.5.3 like this:
   table  : 60 -> 2048
   column : 255 -> 1024
 *http://dev.mysql.com/doc/refman/5.5/en/create-table.html

 actual test result in Server version: 5.5.19-log MySQL Community Server (GPL)
   Caused by: java.sql.SQLException: Comment for table 'member' is too long (max = 2048)
   Caused by: java.sql.SQLException: Comment for field 'REGISTER_DATETIME' is too long (max = 1024)

 ERMaster-b is forked product
 so no problem basically for new version