toastergui: all builds page lists failed build requests

toastergui: all builds page lists failed build requests

This patch modifies the all builds page by splitting the page
into two variants - the "interactive" (default) and "managed" mode
versions.

In the "managed" mode version, we display build requests instead of
builds, including the failed build requests that have no build
associated with them.

[YOCTO #6671]

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