De-normalize new counters from 4.3.0 (#5547)

* Added de-norm counter migration for assets

* Renaming counter columns, since Eloquent has a magical *_count helper

* Added artisan command to sync counters (one-off)

* Update API to use de-normed fields

* Increment counters for checkin;/checkout

* Derp.

* Added request increment/decrementer

* Move increment for checkout to the Asset::checkout method

* Added “could take a while” message

app/Console/Kernel.php

@@ -29,6 +29,7 @@ class Kernel extends ConsoleKernel
         Commands\ResetDemoSettings::class,
         Commands\SyncAssetLocations::class,
         Commands\RegenerateAssetTags::class,
+        Commands\SyncAssetCounters::class,
     ];
 
     /**