[Toaster] [review-request] fixup dependency excludes_set for custom image

[Dave Lerner]

Branch: master
Defect: 9156
Summary: toaster: fixup dependency excludes for customimage

commit b234dae9f3023af71814d9bb8f7052013b9400e8
Author: Dave Lerner <dave.lerner at windriver.com>
Date:   Mon Feb 29 14:58:35 2016 -0600

    toaster: fixup dependency excludes for customimage
    
    [YOCTO #9156]
    
    For a customized image when adding a dependent package X that depends on
    dependency package Y, in addition to adding X to appends_set and Y to
    includes_set, make sure that Y is no longer in the excludes_set. Y may
    have been added to the excludes_set by a prior package removal.
    
    Signed-off-by: Dave Lerner <dave.lerner at windriver.com>


Test setup
----------
Build core-image-sato.
Create a new project 'myproject' on master.
Create a custom image 'myimage' based on core-image-minimal.
Build core-image-minimal.
Customize myimage.

Test steps and expected results
-------------------------------
Search for atk, add the package accept the additional packages.
for each of the following verify that buttons switch to Remove Package:
    glib-2.0, libpcre, libffi, bash
Search for atk, click the remove package button.
for each of the following verify that buttons switch to Add Package:
    glib-2.0, libpcre, libffi, bash

Exit browser then re-enter browser
Pick All-Projects, pick 'myproject', click on Custom image, then select 'myimage'.
Search again for 'atk' and add the package.
for each of the following verify that buttons switch to Remove Package:
    glib-2.0, libpcre, libffi, bash