move apis into rom/modules/main for shell compatibility

sys/modules/opus/bulkget.lua

@@ -0,0 +1,33 @@
+local Util = require('opus.util')
+
+local parallel = _G.parallel
+
+local BulkGet = { }
+
+function BulkGet.download(list, callback)
+	local t = { }
+	local failed = false
+
+	for _ = 1, 5 do
+		table.insert(t, function()
+			while true do
+				local entry = table.remove(list)
+				if not entry then
+					break
+				end
+				local s, m = Util.download(entry.url, entry.path)
+				if not s then
+					failed = true
+				end
+				callback(entry, s, m)
+				if failed then
+					break
+				end
+			end
+		end)
+	end
+
+	parallel.waitForAll(table.unpack(t))
+end
+
+return BulkGet