ignore project-specific config files

Some private stuff.
mysql: try to set more sane defaults (charset)

utf-8 all the way. Please convert first.
pg/bulk: improve error reporting + cleanup

BulkFinish() was returning an error but bulkTransfer() wasn't reporting it.
types: start using constants

Because that's what they are. This also brought an error to light: bit
should be converted to bit varying (and it wasn't even being properly
constructed).
pg: correctly encode timestamp types

Apparently they need single quotes.