Documentation -- Clarified use of 'view' in test client introduction

The line "Test that the correct view is executed for a given URL"
is at best ambiguous: the test client doesn't offer any special support
for determining the view function (or class) that was called. It does
detail the templates that were rendered, but those may or may not be in
a one-to-one relationship with view functions.

There are ways to determine the view function (using `django.core.urlresolvers.resolve`,
for example) but they don't really have anything to do with the test client. (See [here](http://stackoverflow.com/q/3669345/2395796)
for an example of the confusion.)

So the language was clarified to refer specifically to templates. Since
the list of features seemed stunted with only two entries, a new one
was added.