fix --from overriding annex-ignore

Make git-annex get/copy/move --from foo override configuration of
remote.foo.annex-ignore, as documented.

This already worked for remotes supporting hasKeyCheap. For others though,
git-annex copy --from foo would silently not do anything, while
git-annex copy --to foo would use the annex-ignored remote.

Also improved the annex-ignore docs, to reflect that `git-annex get`
without --from will skip using annex-ignored remotes, for example.

Sponsored-by: Dartmouth College's DANDI project

Annex/NumCopies.hs

@@ -317,7 +317,7 @@ pluralCopies _ = "copies"
 verifiableCopies :: Key -> [UUID] -> Annex ([UnVerifiedCopy], [VerifiedCopy])
 verifiableCopies key exclude = do
 	locs <- Remote.keyLocations key
-	(remotes, trusteduuids) <- Remote.remoteLocations locs
+	(remotes, trusteduuids) <- Remote.remoteLocations (Remote.IncludeIgnored False) locs
 		=<< trustGet Trusted
 	untrusteduuids <- trustGet UnTrusted
 	let exclude' = exclude ++ untrusteduuids