tables can be sorted; optimized Agents load slightly
Document `events_to_show` and `ttl`.
DataOutputAgent: Allow the `pubDate` value for each item to be given by user.
update CHANGES.md
fix _response_ description
Merge pull request #491 from cantino/maintain_changes

update CHANGES.md
Merge branch 'master' into table_sorting
integrate knu's suggestions
update CHANGES.md
Merge pull request #488 from knu/data_output_agent-pubDate

DataOutputAgent: Allow the `pubDate` value for each item to be given by user.