Bq date partitioning (#641)

* first cut of date partitioning

* cleanup, implement partitioning in materialization

* update requirements.txt

* wip for date partitioning with range

* log data

* arg handling, logging, cleanup + view compat for new bq version

* add partitioning tests, compatibility with bq 0.29.0 release

* pep8

* fix for strange error in appveyor

* debug appveyor...

* dumb

* debugging weird bq adapter use in pg test

* do not use read_project in bq tests

* cleanup connections, initialize bq tests

* remove debug lines

* fix integration tests (actually)

* warning for view creation which clobbers tables

* add query timeout example for bq

* no need to release connections in the adapter

* partition_date interface change (wip)

* list of dates for bq dp tables

* tiny fixes for crufty dbt_project.yml files

* rm debug line

* fix tests


automatic commit by git-black, original commits:
  4eb75ec

core/dbt/exceptions.py

@@ -104,7 +104,7 @@ def __str__(self, prefix="! "):
         if self.node is not None:
             node_string = " in {}".format(self.node_to_string(self.node))
 
-        if hasattr(self.msg, 'split'):
+        if hasattr(self.msg, "split"):
             split_msg = self.msg.split("\n")
         else:
             split_msg = str(self.msg).split("\n")