ExecutionPlan#result
Basic execution plan web console view
Temporarily remove plans filtering and pagination

Persistence needs to support that first
Use Persistence as a layer between code and a persistence_adapter

It handles the transition between high level objects and their
hash representation in persistence.
Update examples
Add find_execution_plans to persistence drivers
Simple test for web console

Just check that the results are ok (no output validation)
Methods renaming

in Persistence:

    s/load_step_action/load_action/g
    s/save_step_action/save_action/g

in ExecutionPlan:

    s/persist/save/g