docs: fix Workbench images and fix jbpm-docs release notes
(cherry picked from commit 41e8abfc03ed1da08bd4e3ffa04dff3dae5e1277)

Conflicts:

	kie-docs/jbpm-docs/src/main/docbook/en-US/ReleaseNotes.xml
 - initial jBPM docs structure(cherry picked from commit 1965854a67957eacb365b5cda83313374ea24944)

Conflicts: