toaster: refactor the target page

the target (packages) page had to refactored to
allow the displays to differ depending on the caller
namely the license manifest link. Amended to make the
link from the tag rather than the pathname itself.

[YOCTO #6291]
[YOCTO #6079]

Signed-off-by: Farrell Wymore <farrell.wymore@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
toaster: Add performance testing script

This is implemented as a django management command.
For the moment the 'manage.py perf' command will track the toaster
'gui' urls http response code and load time.

To use it:
1. do your toaster builds
2. ensure toaster is started
1. cd bitbake/lib/toaster
2. ln -s ../../../build/toaster.sqlite
3. ./manage.py perf

Signed-off-by: Ionut Chisanovici <ionutx.chisanovici@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
toaster: display message if no images are generated

Display message if no images are generated for a target. This
commit was amended to have more conditions for displaying the
message.

[YOCTO #6094]

Signed-off-by: Farrell Wymore <farrell.wymore@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
toaster: Fix spacing and layout in no image files notification

Close the definition list before adding the notification, and
restrict the notification width to avoid uncomfortable line
lenghts.

Signed-off-by: Belen Barros <belen.barros.pena@intel.com>
Signed-off-by: Alexandru DAMIAN <alexandru.damian@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>