cached_property's topic documentation does not link to reference

[Baptiste Mispelon]

The paragraph at ​https://docs.djangoproject.com/en/dev/topics/performance/#cached-property does not link to the reference documentation at ​https://docs.djangoproject.com/en/1.8/ref/utils/#django.utils.functional.cached_property.

In particular, it does not mention the import path.

This is especially a problem because the performance page appears before the reference page in a search for cached_property.

I think having the text @cached_property in the sentence Using the @cached_property decorator saves the value returned [...] be a link should be enough.

[Tim Graham <timograham@…>]

In e0de82c:

Fixed #25727 -- Added a doc link to cached_property.

[Tim Graham <timograham@…>]

In f1022623:

[1.9.x] Fixed #25727 -- Added a doc link to cached_property.

Backport of e0de82c9b2c41c4c479d2245e7d5cd59638b5440 from master

[Tim Graham <timograham@…>]

In e592574:

[1.8.x] Fixed #25727 -- Added a doc link to cached_property.

Backport of e0de82c9b2c41c4c479d2245e7d5cd59638b5440 from master