Move students controller spec subject from Profile V1 to V2
Move students controller spec subject from Profile V1 to V2

+ Authorization specs remain the same
+ No need to test server-side CSV rendering
+ Test assignment of student serialized data
+ #211

erose/studentinsights,jhilde/studentinsights,studentinsights/studentinsights,erose/studentinsights,jhilde/studentinsights,erose/studentinsights,studentinsights/studentinsights,jhilde/studentinsights,jhilde/studentinsights,erose/studentinsights,studentinsights/studentinsights,studentinsights/studentinsights