BUG: ApplyChanges should only execute a single query for multiple changes to a single record.

[rathboma]

If you change 3 fields of a record, then apply (or copy to SQL), Beekeeper will generate 3 separate update queries. It should instead only generate a single query per record.

Bad

UPDATE mytable SET a = 'a' WHERE id = 1;
UPDATE mytable SET b = 'b' WHERE id = 1;
UPDATE mytable SET c = 'c' WHERE id = 1;

Good

UPDATE mytable SET a = 'a', b = 'b', c = 'c' WHERE id = 1

This might require some real refactoring of the change builder classes, not sure.