Upgrades built into morf-core should be tidied to cover only creation of morf supporting tables

[badgerwithagun]

See https://github.com/alfasoftware/morf/tree/master/morf-core/src/main/java/org/alfasoftware/morf/upgrade/upgrade - I think we just want the upgrades to create the UpgradeAudit and DeployedViews tables from scratch so there is a clear route for adding morf to existing applications.

[harrisric]

Mainly done under #270
Nothing superfluous in morf upgrade steps now.
Missing anything that creates UpgradeAudit but I'm not sure that bootstrapping is necessary.