[CDBI] Addition of store method

[David Steinbrunner]

Michael G Schwern wrote:

> Sounds like MySQL's "INSERT ... ON DUPLICATE KEY UPDATE"

Right.

Having such a store method overridden on the CDBI::mysql level would likely
be a good idea to take advantage of that syntax, too.  Currently I would
like to just have the feature in place and then optimizations at the DBD
level could be taken into consideration.

--
David Steinbrunner