change tense is some of the outputs so it's consisent

Author: tabacitu

src/Console/Commands/ConfigBackpackCommand.php

@@ -67,7 +67,7 @@ public function fire()
         $path = $this->getPath($name);
 
         if ($this->alreadyExists($this->getNameInput())) {
-            $this->error($this->type.' already exists!');
+            $this->error($this->type.' already existed!');
 
             return false;
         }

src/Console/Commands/CrudModelBackpackCommand.php

@@ -130,7 +130,7 @@ public function handle()
             }
 
             // In case we couldn't add the CrudTrait
-            $this->error("Model already exists on '$name' and we couldn't add CrudTrait. Please add it manually.");
+            $this->error("Model already existed on '$name' and we couldn't add CrudTrait. Please add it manually.");
         }
     }
 

src/Console/Commands/ViewBackpackCommand.php

@@ -71,7 +71,7 @@ public function fire()
         $path = $this->getPath($name);
 
         if ($this->alreadyExists($this->getNameInput())) {
-            $this->error($this->type.' already exists!');
+            $this->error($this->type.' already existed!');
 
             return false;
         }