Add config parameter to disable statement escaping

Add statement_escape_processing parameter, that when set to false
disables JDBC escaping by calling setEscapeProcessing(false) on the
Statement.
disable statement escape processing by default + hide createStatement
+ logically re-arrange execute Java methods
[mysql] #indexes compatible with 4.0 as well as #pk_and_sequence_for
- primary_key now using JDBC API directly + save an array on #columns