Bug 9969

The display of target:task in the build dashboard, all builds, project builds etc. pages is inconsistent and poorly-implemented.

Because different model and template methods are used in different places, in some parts of the application, we show the target only (e.g. title for build dashboard), while in others we show target + task (e.g. all builds table).

Places where this is definitely needed:

bitbake/lib/toaster/toastergui/templates/basebuilddetailpage.html
bitbake/lib/toaster/toastergui/templates/builddashboard.html
bitbake/lib/toaster/toastergui/templates/basebuildpage.html
bitbake/lib/toaster/toastergui/templates/target.html

(NB the mrb section also displays target:task, but this is now fetched from the mostrecentbuilds API - see below.)

The fixes for 9631 include an API for getting recent builds data (mostrecentbuilds), which has some code for creating the target:task list. We also have a Build.get_sorted_targets_list() method which does part of the job.

Rationalise the code from those two places and move it to the Build model (perhaps with a custom template tag which we can also call from the mostrecentbuilds API); then apply across all parts of Toaster where we should be showing "target:task, target:task, ...".