The Postgres and MySQL plugins should run *.sql files like a SQL client

[joakimbeng]

Currently the Postgres and MySQL plugins runs *.sql files using multi statement queries which is bad because it can't run database dumps containing DELIMITER statements, which dumps with stored procedures and similar contains.

To be able to run such migration files the different plugins needs to be able to split a query into statements based on ; and DELIMITER statements.

Splitting files into statements and running each statement in order also opens up possibilities to report progress per statement and affected rows and such. The plugins could also report exactly which statement that failed in case of an error.