Text summary isn't hidden/shown in 1.9+

Links to show and hide text summary fields don't work using jquery 1.9+ since the toggle() behavior that text.js relies upon was removed after 1.8.

Attached is a fixed version of text.js that simply uses click(), but there's no analog for replacing a core module's javascript file in jquery_update thus far, so i'm not sure what the best way to implement the replacement would be.

It's also possible #2156881: Support (optionally) the use of the jQuery Migrate Plugin would fix this issue, but I haven't tested that. Even if it does, that patch requires that the migrate plugin be explicitly enabled. The show/hide text summary link is a core feature which is broken out of the box with jquery update and it doesn't seem like a non-default setting should be required in order to make it not broken.