Disable dragging dashcards when not in edit mode on mobile.

Resolves #2212

style tweaks.

add migration to fix any dashboard cards with NULL :row or :col values.

make sure we have a default value for `metabot-enabled`

XKCD Chart Easter Egg

New dashboard grid size + scalable cards + fullscreen + auto refresh

Metabot final touches

fix data reference scrolling

Merge branch 'new-dash-plus-scalable-cards-plus-fullscreen' of github.com:metabase/metabase into new-dash-plus-scalable-cards-plus-fullscreen

Merge branch 'new-dash-plus-scalable-cards-plus-fullscreen' of github.com:metabase/metabase into new-dash-plus-scalable-cards-plus-fullscreen

Conflicts:
	src/metabase/db/migrations.clj

how do parens work?

Contributor guide

Merge branch 'master' of github.com:metabase/metabase into new-dash-plus-scalable-cards-plus-fullscreen

Conflicts:
	src/metabase/db/migrations.clj

Merge branch 'new-dash-plus-scalable-cards-plus-fullscreen' of github.com:metabase/metabase into new-dash-plus-scalable-cards-plus-fullscreen

update slack api settings endpoint to handle `metabot-enabled` setting and add a new metabot-lifecycle event handler which can listen for the appropriate events (:settings-update) and trigger startup/shutdown of metabot as needed.

add a new setting for `metabot-enabled` which defaults to true and only launch metabot when it's enabled.  also, remove printlns and tidy up logging a bit.

Disable field type