MDL-57791 analytics: Changes after review

- Split model::predict in parts
- JS promises updated according to eslint-plugin-promise
- New API methods replacing direct DB queries
- Reduce insights nav link display cost
- Increase time limit as well as memory for big processes
- Move prediction action event to core
- Dataset write locking and others
- Refine last time range end time
- Removed dodgy splitting method id to int
- Replace admin_setting_predictor output_html overwrite for write_setting overwrite
- New APIs for access control
- Discard invalid samples also during prediction

lib/db/caches.php

@@ -312,8 +312,8 @@ $definitions = array(
         ),
     ),
 
-    // Caches analytic models that have already predicted stuff.
-    'modelswithpredictions' => array(
+    // Caches contexts with insights.
+    'contextwithinsights' => array(
         'mode' => cache_store::MODE_APPLICATION,
         'simplekeys' => true,
         'simpledata' => true,