fix source and use pry-debundle
qualify_to is deprecated
Fix foreign keys schema file. It's not used though.
allow dump of a single table
bump version
Make restore work better.

Refactor so that it's an enumerator when reading a dump file.
Use a Sequel private API :-O to greatly speed up restore.
depend on sequel ~> 4.0.0
move make_pump to a module, and fix initialize for (Dump|Restore)Schema
Don't create a dump file for empty tables.
container is an accessor of RestoreSchema
fix restore_table to use newer DbPump
add executable
update docs and bump version