Merge both functions for creating mongodb containers into one.
Add retries to docker container cleanups.
Require $VAULT_ACC be set to enable AWS tests.
* redoing connection handling
* a little more cleanup
* empty implementation of rotation
* updating rotate signature
* signature update
* updating interfaces again :(
* changing back to interface
* adding templated url support and rotation for postgres
* adding correct username
* return updates
* updating statements to be a list
* adding error sanitizing middleware
* fixing log sanitizier
* adding postgres rotate test
* removing conf from rotate
* adding rotate command
* adding mysql rotate
* finishing up the endpoint in the db backend for rotate
* no more structs, just store raw config
* fixing tests
* adding db instance lock
* adding support for statement list in cassandra
* wip redoing interface to support BC
* adding falllback for Initialize implementation
* adding backwards compat for statements
* fix tests
* fix more tests
* fixing up tests, switching to new fields in statements
* fixing more tests
* adding mssql and mysql
* wrapping all the things in middleware, implementing templating for mongodb
* wrapping all db servers with error santizer
* fixing test
* store the name with the db instance
* adding rotate to cassandra
* adding compatibility translation to both server and plugin
* reordering a few things
* store the name with the db instance
* reordering
* adding a few more tests
* switch secret values from slice to map
* addressing some feedback
* reinstate execute plugin after resetting connection
* set database connection to closed
* switching secret values func to map[string]interface for potential future uses
* addressing feedback
* Start work on context aware backends
* Start work on moving the database plugins to gRPC in order to pass context
* Add context to builtin database plugins
* use byte slice instead of string
* Context all the things
* Move proto messages to the dbplugin package
* Add a grpc mechanism for running backend plugins
* Serve the GRPC plugin
* Add backwards compatibility to the database plugins
* Remove backend plugin changes
* Remove backend plugin changes
* Cleanup the transport implementations
* If grpc connection is in an unexpected state restart the plugin
* Fix tests
* Fix tests
* Remove context from the request object, replace it with context.TODO
* Add a test to verify netRPC plugins still work
* Remove unused mapstructure call
* Code review fixes
* Code review fixes
* Code review fixes
* database/mysql: Allow the creation statement to use commands that are not yet supported by the prepare statement protocol
* Remove unnecessary else block
* Fix the mysql legacy username length
* Remove boolean parameter
* Add a MySQL 5.6 container to test the legacy MySQL plugin against
* Add database plugins to the make file
* Fix credsutil test
