implementing drag and drop sorting as work around for collection fetch issue
got drag and drop sorting working
imporved style for task list 'table'
cleaned up backbone model and task controller methods no longer being used, cleaned up routes accordinly
implemented jQuery datepicker for task due date, improved handling of duedate values so API wouldn't reject them
Merge branch 'draganddrop' into backbone
improved due date validation a bit
ensured that row with 'you have no tasks' message shows when you have no tasks
improved styles for completed tasks, cleaned up task view a bit
tweaked font size for task due date a bit