[API 7.0.0 compatibility] Made changes to take advantage of the latest API changes

including the ability to start and stop most scripts.

examples/hello_world.lua

@@ -31,7 +31,20 @@ local du = require "lib/dtutils"
 
 du.check_min_api_version("2.0.0", "hello_world") 
 
+-- script_manager integration to allow a script to be removed
+-- without restarting darktable
+local function destroy()
+    -- nothing to destroy
+end
+
 dt.print("hello, world")
 
+-- set the destroy routine so that script_manager can call it when
+-- it's time to destroy the script and then return the data to 
+-- script_manager
+local script_data = {}
+script_data.destroy = destroy
+
+return script_data
 --
 -- vim: shiftwidth=2 expandtab tabstop=2 cindent syntax=lua