add option showdate

add option showdate:yes|no
to show/hide start/due-date

<todo showdate:yes>...</todo>
add showdate
add showdate
add option showdate:yes|no
bugfix

value of $data['showdate'] was not set correctly
bugfix

value of $data['showdate'] was not set correctly
seperate showdate tag/list
seperate showdate tag/list
add showdate tag/list
add showdate tag/list