TUNIS, June 16 (Reuters) - Three of the ten Tunisian consular staff kidnapped in Libya last week have been freed and negotiations over other hostages are continuing, a Libyan official and a Tunisian source said on Tuesday. Gunmen stormed the consulate in Tripoli on Friday. Tunisia is one of the few countries to still have a diplomatic presence in Tripoli since an armed faction called Libya Dawn took over the capital and forced out the internationally recognised government that **w operates from the east. ...