Add icons to "select-all" and "select-none" buttons in the journal

Signed-off-by: Walter Bender <walter@sugarlabs.org>
The .view insensitive should not have the same grey than the entry

Signed-off-by: Gonzalo Odiard <gonzalo@laptop.org>
Merge pull request #8 from godiard/journal_multiselection-try2

Add icons for the Journal multiselection toolbar