Remove skip for fixtures.

I'll be fixing fixtures so this needs to be removed.
Start updating fixtures to use new Schema system.
Always set configKeyName on connections.

This is useful in fixtures for figuring out where a fixture was added.
This property will hopefully be removed, but for now it is a necessary
crutch.
Add stub method for reseting sequences.

This method needs to be implemented, but first sequence reflection needs
to be implemented in schema + postgres.
Update create + insert methods.

Update methods + tests for creating and inserting fixture records.
Add dropTableSql()

Add tests for MysqlSchema + Table.
Add dropTableSql to Postgres.
Add dropTableSql to Sqlite.
Rename methods on Table class.

The word Table is redundant in these methods.
Update dropTableSql methods to return an array of queries.

This makes this method consistent with the createSql method, and
the upcoming truncateSql methods.
Add table truncation for sqlite + mysql

Fixtures need to be able to truncate tables, we'll need this code
for that.
Very naive implementation of table truncation with postgres.

I'm fairly certain that sequence names will need to be generated/handled
as the auto generated names are very unlikely to be the names given
to addConstraint()
Update TestFixture and implement truncate() with new code.
Update the first fixture to use new constraints key.

Many more fixtures will need to be updated.
Use RESTART IDENTITY

It is far less janky than trying to guess sequence names.
Fix errors when columns match value lengths.
Add a method to get the schema collection.

This makes mocking simpler, and doesn't force callers to construct
a Schema\Collection making a hard dependency.
Multi-row insert's do not work in Sqlite right now.

I've fixed some of the issues but not all of them. There is
still a problem with nulls being inserted in every column.
Update usage of Query() class and fix insertion errors.

Fix errors inserting records (there are still remaining issues with
SQLite).
Make fixtures work again.

New style static fixtures now work in MySQL.