[Toaster] Review request - Front-end fixes

[Barros Pena, Belen]

I have a small set of front-end fixes for review at

http://git.yoctoproject.org/cgit/cgit.cgi/poky-contrib/commit/?h=bbarrosp/f
ront-end-120314

They:

* Set the href for the Toaster manual link to the correct URL
* Fix some small spacing issues in the filter dialogs and the breadcrumb
* Change a label in the installed package details page to make it
consistent with the rest of Toaster
* Apply the failed filter when applicable to the link in the Failed tasks
info in the builds table
* Make sure the "Cache attempt" column is part of the default column set
in the tasks table

Thanks!

Belén