title: Do i need to install entity framework every time when i used mvc 4 with ef..?
body: <p>i have done one demo project on mvc 4 using entity framework and heading to second on, but when i use DbContext class i get error like : 
  The type or namespace name 'DbContext' could not be found (are you missing a using directive or an assembly reference?).
  Even if i added System.Data.Entity.dll...
  When search on internet, many told to install entity framework from Nu get, but i install it in previous project. So do i need to install it every time when i use MVC using EF..??
  Anyone please help...</p>