current bitbake-diffsigs simply print out the whole 'runtaskdeps' when there's mismatch, which
is not very readable. On the other hand, 'runtaskhashes' comparison is broken which assumes
same key existing in two sides. This commit provides better output by figuring out differences
from addition, removal or hash change.
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
bcb1873836