Exasol-cdc support rename table, drop table, drop column, rename column

truncate table
drop table
rename table
alter table drop column
alter table rename column

Basic support for alter table add column. The types sent to exasol are exactly the same as the ones in the received sql. These will have to be converted, which will be done in https://jira.mariadb.org/browse/MXS-6557.