Grammar/Vocabulary fixes

Signed-off-by: Chris Berthe <chrisberthe@gmail.com>

laravel/database/schema.php

@@ -71,7 +71,7 @@ class Schema {
 	{
 		// The implications method is responsible for finding any fluently
 		// defined indexes on the schema table and adding the explicit
-		// commands that are needed to tbe schema instance.
+		// commands that are needed for the schema instance.
 		static::implications($table);
 
 		foreach ($table->commands as $command)