Add following features and improvements:
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1. Display today's date on the top of the screen

2. Move "Add New Item" widget from the bottom of the screen to the top, so that the pop-up keyboard will not block the edit text view

3. When a new item added into the list without a "due date", a Calendar icon will be displayed to remind users to set due date. (see screenshot 1)

4. When user clicks one line item to open up the edit screen, besides the original DatePicker that supports selecting a due date, a new checkbox is added to this screen to allow user to indicate if the item is done. (see screenshot 2)

5. Once user saves all his edits and returns to main screen, item list will be updated accordingly (see screenshot 3):
 - If an item is NOT done and has NOT passed the due date, a yellow "On Hold" indicator will be displayed for this line item.
 - If an item is NOT done but has passed the due date, a red "cross" indicator will be displayed for this line item.
 - If an item is done, regardless the due date being passed or not, a green "check" indicator will be displayed for this line item.
 - The calendar icon will be displayed by the due date string that user just selected. If user did not pick a due date before returning to this screen, calendar icon remains

Signed-off-by: Cindy T. Li <cindyltq@hotmail.com>