Introduces flow types for storage (#4349)

* Introduces flow types for storage

* Better typing of QueryOptions

* Adds flow types to SchemaCOntroller,

- runs flow on pre tests
- fixes flow

* Adds ClassLevelPermissions type

* Moves Controller types into a single file

* Changes import styles

* Changes import styles

* fixing method setIndexesWithSchemaFormat (#4454)

Fixing invalid database code in method `setIndexesWithSchemaFormat`:

* It must be a transaction, not a task, as it executes multiple database changes
* It should contain the initial queries inside the transaction, providing the context, not outside it;
* Replaced the code with the ES6 Generator notation
* Removing the use of batch, as the value of the result promise is irrelevant, only success/failure that matters

* nits

* Fixes tests, improves flow typing

src/Controllers/HooksController.js

@@ -1,7 +1,9 @@
 /** @flow weak */
 
 import * as triggers        from "../triggers";
+// @flow-disable-next
 import * as Parse           from "parse/node";
+// @flow-disable-next
 import * as request         from "request";
 import { logger }           from '../logger';
 
@@ -28,7 +30,7 @@ export class HooksController {
   }
 
   getFunction(functionName) {
-    return this._getHooks({ functionName: functionName }, 1).then(results => results[0]);
+    return this._getHooks({ functionName: functionName }).then(results => results[0]);
   }
 
   getFunctions() {
@@ -36,7 +38,7 @@ export class HooksController {
   }
 
   getTrigger(className, triggerName) {
-    return this._getHooks({ className: className, triggerName: triggerName }, 1).then(results => results[0]);
+    return this._getHooks({ className: className, triggerName: triggerName }).then(results => results[0]);
   }
 
   getTriggers() {