Merge pull request #10 from khepin/readme

Update readme with "what this is for"

README.md

@@ -6,6 +6,10 @@ Eloquent Mutators
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+This package allows you to map your model attributes to database columns when the type in the PHP model does not match the type in the database column.
+
+This could be using `$model->ip_address` as a `string` in your eloquent model but storing it as a `BINARY(16)` in the database for efficiency. Or having a string always encrypted in the DB but readable in clear form within your models.
+
 Installing
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