Manage entries at scale

- the admin uses the full window width, table cells stop wrapping
- columns sort by number, title, project, status, date and author
- filters sit in one row with search first and a page size next to them
- entries carry a real date: publish_at on create and change, publishing
  keeps that date, a date in the past publishes backdated

messages/en.json

@@ -343,7 +343,8 @@
 				"search": "Search",
 				"searchPlaceholder": "Title and teaser",
 				"submit": "Apply",
-				"reset": "Reset filter"
+				"reset": "Reset filter",
+				"perPage": "Per page"
 			},
 			"status": {
 				"draft": "Draft",
@@ -374,7 +375,7 @@
 				"slug": "Part of the address in the archive. Leave it empty to derive it from the title.",
 				"cover": "Sits large above the entry. Without an image the plate takes that space.",
 				"drop": "Drag images here or paste them with Ctrl+V, several at once works.",
-				"schedule": "A moment in the future. The entry appears automatically once it is reached.",
+				"schedule": "A date in the future publishes the entry automatically. A date in the past publishes it right away, carrying that date.",
 				"projectMove": "On a move the entry receives the next free number in the target project."
 			},
 			"save": {