ui/knotty: Add a footer to the build output for interactive terminals as knotty2 UI

ui/knotty: Add a footer to the build output for interactive terminals as knotty2 UI

On terminals which support it, add summary information to the end of the
build output about the number of tasks currently running and how many tasks
we've run so far.

This provides a summary at a glace of what the current state of the build is
and what the build is currently doing which is lacking in the current UI.

Also disable echo of characters on stdin since this corrupts the disable,
particularly Crtl+C.

The "waiting for X tasks" code can be merged into this code too since
that is only useful on interactive terminals and this improves the
readability of that output too.

Improvements since v0:

* The tasks are ordered in execution order.
* The display is only updated when the list of tasks changes or there
  is output above the footer.
* Running task x oy y and package messages are supressed from the console

This UI can be accessed with "bitbake -u knotty2".

(From Poky rev: e38b4569648f2916c4370871c79e6a6090eb8bc1)

(Bitbake rev: 156189c799d2bb1f69bdaa04b5cd718fe7881425)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>