docs(guide/e2e-testing): clarify description of input(name) selector

The description of the input selector made it seem that you were selecting
an input element based upon it's name attribute. In reality, you are
selecting an element by the string in the ng-model attribute.

Author: Gwash3189

docs/content/guide/dev_guide.e2e-testing.ngdoc

@@ -110,16 +110,16 @@ Scopes the next DSL element selection.
 Returns the value of the first binding matching the given `name`.
 
 ## input(name).enter(value)
-Enters the given `value` in the text field with the given `name`.
+Enters the given `value` in the text field with the corresponding ng-model `name`.
 
 ## input(name).check()
-Checks/unchecks the checkbox with the given `name`.
+Checks/unchecks the checkbox with the corresponding ng-model `name`.
 
 ## input(name).select(value)
-Selects the given `value` in the radio button with the given `name`.
+Selects the given `value` in the radio button with the corresponding ng-model `name`.
 
 ## input(name).val()
-Returns the current value of an input field with the given `name`.
+Returns the current value of an input field with the corresponding ng-model `name`.
 
 ## repeater(selector, label).count()
 Returns the number of rows in the repeater matching the given jQuery `selector`. The `label` is