Fix suggest directory widgets to display full path of hierarchical vocabulary

When using a selectOne/ManyDirectory widgets on a hierachical vocabulary (such as l10ncoverage, l10nsubjects), the selected entries in view mode were displayed like:

• Art/Cinema
• Europe/France

With the suggestOne/ManyDirectory widgets, the selected entries are like:

• Cinema
• France

i.e. the full path is not displayed, only the label of the leaf entry.

suggestOne/ManyDirectory widgets must behave like selectOne/ManyDirectory ones.