lib/bb/siggen: show word-diff for single-line values containing spaces

If a variable value has changed and either the new or old value contains
spaces, a word diff should be appropriate and may be a bit more readable.
Import the "simplediff" module and use it to show a word diff (in the
style of GNU wdiff and git diff --word-diff).

Also use a similar style diff to show changes in the runtaskhashes list.
I didn't use an actual word-diff here since it's a little different - we
can be sure that the list is a list and not simply a free-format string.

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 2 insertions, 0 deletions

diff --git a/LICENSE b/LICENSE
index 5d4a4c2a8..7d4e5f44b 100644
--- a/LICENSE
+++ b/LICENSE
@@ -15,3 +15,5 @@ Foundation and individual contributors.
 * QUnit is redistributed under the MIT license.
 
 * Font Awesome fonts redistributed under the SIL Open Font License 1.1
+
+* simplediff is distributed under the zlib license.