Allow to set due date for items

This change allows to set a due date for top level items and todos. The
due date is visible in the item's page. In addition, there's an overlay
for top level items. For todos, the due date is shown in the todo
listing.
15 jobs for 162-allow-to-set-due-date-of-items in 6 minutes and 14 seconds (queued for 1 second)
Status Job ID Name Coverage
  Images
manual #46376742
allowed to fail manual
build_image_fedora
manual #46376743
allowed to fail manual
build_image_fedora_system
manual #46376744
allowed to fail manual
build_image_ubuntu
manual #46376745
allowed to fail manual
build_image_win32
manual #46376747
allowed to fail manual
build_image_win64
 
  Build
passed #46376750
linux_builtin

00:03:21

passed #46376751
linux_system

00:04:19

manual #46376757
macos allowed to fail manual
macos
passed #46376752
ubuntu_appimage

00:06:13

passed #46376753
win32_build

00:04:32

manual #46376755
windows allowed to fail manual
win32_vs_build
passed #46376754
win64_build

00:06:03

manual #46376756
windows allowed to fail manual
win64_vs_build
 
  Installer
manual #46376758
allowed to fail manual
win32_vs_installer
manual #46376759
allowed to fail manual
win64_vs_installer