Add Support for Views

Initial support to incorporate view creation and use alongside Sqlalchemy.

• Support for View classes that emit creation/drop DDL.
• Automatically recognize View dependencies from the selectable query that generates the view.
• Add helper to create schemas before creating a MetaData's table objects.

Server side updated_at, created_at

• Trigger statement compilers for "before row update" and "drop trigger."
• Declarative base audit mixin for appending a created_at and updated_at in UTC on the server side.

Primary Key Upsert

Add function to generate insert when the primary key doesn't exist, otherwise, update for a sqlalchemy table.

Delete records when not in refresh statement

Helper query builder to delete records in a table when a refresh statement or table does not have rows existing via the source table's primary key columns.

Expression compilation

• Helpers to compile Sqlalchemy expressions to strings.

Minor additions

• Helper for quickly querying a table's row count with an optional conditional argument. Can be used to verify if third-party data refreshed properly.

0.0.7

• Added helpers for filtering columns with Python or database side defaults.

UUID Server Functions

• Implement UUID type without as_type configuration option
• Postgres server side UUID generation for random and sequenced UUID's
• small cleanups and test fixes.

Integrate postpy

• Integrate functionality for schema ddl statements and testing fixtures from postpy
• Add alchemy.schema utility specification
• incorporate code coverage with travis

Test Fixture

• Test fixture now only configurable through env variables.