Add some helper methods to deal with sqlite migrations

SQLite has very little support for altering tables.  Add some helper
methods mostly written by Sergey Lukjanov to work around these
issues.

Change-Id: I4a68fc0d6291e72c88c511d5f64befa41363df2c
Co-Authored-By: Sergey Lukjanov <slukjanov@mirantis.com>
Merge "Add some helper methods to deal with sqlite migrations"