adding submenus functionality to the menu service

When having few modules like Articles, Blog, Services, etc... it's good to add the 'New Whatever' or other functionalities within a submenu structure.
updating calls to addMenuItem and addSubMenuItem

We can still create normal MenuItems without the 'dropdown' class.
Create dropdown on menuitems with submenus
little fix on removeSubMenuItem()
minor change on addMenuItem
minor fixes on client view
Create Task module using yo meanjs:crud-module
Reformat and bootstrappify the client home view.
Add a little info about the sample app
Changed all the indents to the spaces(tab size 4)
Typo in test message:
Remove unneeded commas in gruntfile.js
grunt build application.min.js
Change uglify mangle option to true
Chage name to AGILEVER
Merge branch 'master' of heroku.com:agilever-stage into dev
Change brand to AGILEVER
grunt build
Merge branch 'pr/60' into 0.3.1
Merge branch 'pr/61' into 0.3.1