Small updates in labels and associate activities with software
Merge with upstream
Update labels (instance) and associate activities with agent

- Update `prov:label` in `niiri:contrast_standard_error_map_id`,
`niiri:extent_threshold_id` to have instance-specific labels
- add a wasAssociatedWith relationship between all activities and
software agent.
Updates suggestion on NIDASH call 03/02/2014

* Change `scaled data` into `data`
* Store the first-level mean BOLD intensity
* Add a png visualisation of the design matrix.
Merge pull request #25 from cmaumet/spmUpdate

Update SPM data model