Changed check_min_api_version() to print error messages and throw an error if the minimum api is not satisfied. Updated the scripts to reflect the changed check_min_api_version().

examples/running_os.lua

@@ -28,10 +28,7 @@ prints the operating system
 local dt = require "darktable"
 local du = require "lib/dtutils"
 
-if not du.check_min_api_version("5.0.0") then
-  dt.print("ERROR:running_os not loaded.  Lua API version 5.0.0 or greater required.")
-  return
-end
+du.check_min_api_version("5.0.0", "running_os") 
 
 dt.print("You are running: "..dt.configuration.running_os)