simplePaginate() incorrect limit

simplePaginate(4) will return `limit 5 offset 0` for page 1 and `limit 5 offset 4` for page 2. This causes next page to show a duplicate from previous page.

Expected result of simplePaginate(4) should be `limit 4 offset 0` for page 1 and `limit 4 offset 4` for page 2 respectively.

Unless I am missing something?