changes made in onetimesale create screen because of date issue

Hi Kiran.

 In this pull request i have made some changes in, onetime sale html and controller file, 
Reason: when we were selecting item code while creating one time sale . the date was getting refreshed and was being set as current date, which was not feasible . so i changed it and fixed that issue. because of this issue i had also changed the platform code, where i removed those statements in constructors where we was returning new LocalDate object ,