add test for 'timetable' directive

add a new Grunt task named 'test:start'
add test for 'timetable' directive
add test for 'TimetablesCtrl' controller
use ngResource module
add resolve definition for 'dash.timetables' state to pre-load timetables
add dependency 'timetables' to 'TimetablesCtrl', which is resolved by ui-router
add pagination code to 'TimetablesCtrl' controller
rename view mode of 'timetables' view 'gallery_extended' to 'gallery-extended'
delete scrollTop(0) from the 'update' event listener of 'scrollbar' directive
fix the bug of 'timetable' directive that a timetable is not rendered correctly if the break time is not 0
rename the file name of template for 'timetable' directive, which was 'dash_timetable.html' to 'timetable.html'
add jQuery wrappers in 'timetable' directive code to pass the unit tests
fix 'timetable' directive not to render timetable when display or classes attribute is null or undefined
fix CSS to style objects with 'timetable' directive as attribute correctly
add view switcher for 'timetables' view
add ui-view directive object to 'timetables' view
update karma.conf.js to use base path 'app'
update karma.conf.js to include template files and perfect-scrollbar library
delete debugger statement from the test code for 'Account' service