Introduce InstancePoolTrait
Move Instance Pool from PEER to TableMap (WIP)
Forward ported PR 560, Fixes #333

Change included by the port is to allow range queries on table
primary key fields, using min/max
Merge pull request #337 from mhitza/pr-327

Forward ported PR 560, Fixes #333
wip move instance pool
wip move peer, fix errors with DSN TableMap loaded