Remove - 'Skip closed hours...' from Loan Policy Editor

Purpose: To remove the field label and associated check-box for 'Skip closed hours in intervening period' from the Loan Policy Editor.

In discussions with the Resource Access SIG (Oct. 11, 2018), the group could not determine any use-cases beyond those already covered by other planned functionality in 'Closed due date management', and recommended removing this option from the Loan Policy Editor altogether.

The option currently appears in the form when Loanable=Y

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Testing:
1) Ensure that the field is no longer present in the form for existing saved Loan Policies
2) Ensure that the field is not present in the form when creating a new Loan Policy
3) Ensure that a default selection is not present in a saved form, even when the field is not present in the Loan Policy Editing interface

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To do:
1) Create a new issue, as necessary, for any back-end changes required to ensure that the field and values are no longer stored server-side