- separated materials TOC into its own bean
- generalised MaterialNode
Merge branch 'FTR-50-WORKSPACE-VIEWS' of https://github.com/otavanopisto/muikku into FTR-50-WORKSPACE-VIEWS
Merge branch 'FTR-50-WORKSPACE-VIEWS' into FTR-44_material-editor

Conflicts:
	muikku-core-plugins/src/main/java/fi/muikku/plugins/workspace/WorkspaceMaterialsBackingBean.java