Add model validator in Controller

Comparing #3 with #4

Content

There are cases that model validators arshould be depended by controller/action and you cannot
 
ouldn't manipulated on the model class or using scenarios in easy way

For example, when inserting a new record we want the controller/action to deside whether or not a validator (or more than one) should be applied.

So a robust way to do that is by insert a validator to the model on Controller/action
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