oppurtunity reopen

1. Only allow users with the user role of System Administrator to have access to the Reopen Opportunity action button available on the Opportunity.

2. Once an Opportunity is closed of all the input data fields available on the

    Opportunity should become read only.

3. When a System Administrator clicks on the Reopen Opportunity button on an Opportunity. The Opportunity should reopen, and all the fields that were made read only should now become editable. Also the system administrator should be able to update the data Save and Reclose the Opportunity.