Changed the welcome screen

Now the welcome screen shows all tasks that are due that today or
within the period of today. Allowing user to see what he needs to do
for today.
Merge branch 'welcome_message'
#76 fix failed test DatePairTest.endDateStartBoundary2()
Merge branch 'tentative_task'
Merge branch 'master' into tentative_task
Fix confirm non-tentative task show proper response