LP #1557440: speedup pt-online-schema-change dropping and recreating secondary indexes

**Reported in Launchpad by Miguel Angel Nieto last update 07-04-2017 17:31:28

There is a feature in Percona Server (expand_fast_index_creation) that the tool cannot use, because there is no "ALTER TABLE" involved. That feature drops the secondary indexes, then run the alter, and create them back again. We should have a parameter that could enable the tool to do something similar:

• CREATE NEW TABLE WITHOUT SECONDARY INDEXES...
• COPY ROWS
• ADD SECONDARY INDEXES
• RENAME

This would make the process much faster.