Fix rails dbconsole for jdbcmysql adapter.
Merge pull request #14985 from eileencodes/refactor-delete-all-method

refactor and clean up delete_all method
Merge pull request #14984 from jkingdon/add-jdbcmysql

Fix rails dbconsole for jdbcmysql adapter
Consolidate common shared to_formatted_s method

Core extensions for Date and Time both included identical code
for to_formatted_s. So, following convention established by
other date_and_time shared methods, I extracted it out into
a common module.
WIP reformat to_formatted_s docs