[642] Fix error with inventory.jobs getting converted to string when saving the Group itself. Fix saving of publish_date when from CSV. Fix display of publish_date in dataset/read.

Conflicts:
	ckanext/dgu/controllers/inventory.py
[642] Publication Date field is now validated on import and only displayed if a proper date. Those that have uploaded non-dates will not see them at dataset/read.
[642] Convert dates to the preferred format in the DB, as used for other date fields.
[642] Search box is "Results" on /data and /data/search and never "total datasets" as that would confuse with number of Datasets on the home page.
[642] Fix cherry-pick from stable.
[642] Cope with ints in XLS dates.
[642] Enable feedback for published datasets
Merge branch 'inventory-stage-2' of github.com:datagovuk/ckanext-dgu into inventory-stage-2
[642] Change wording on add form for published datasets
[642] Fix full stops.
[noticket] Fix for Victoria & Albert Museum not being able to download template due to missing encoding

Conflicts:
	ckanext/dgu/controllers/inventory.py
Merge branch 'stable' into inventory-stage-2

Conflicts:
	ckanext/dgu/controllers/inventory.py
	ckanext/dgu/theme/timestamp.py