Fix typo. Improve consistency. Change some translations choices.

Disambiguate Add/Insert which were both translated as Add.
Change colloquial 'Ci sono dei problemi' with 'Sono stati riscontrati' to be more consistent with previous translation where 'riscontrati' where used.
Dashboard acquires feminine gender in italian, change article to reflect this rule.
Instead of 'indietro', use the more direct 'Torna' which means 'go back to'.
Change 'ha' (has) with 'dispone di' (more commonly used for file/folder permissions) to be consistent with the rest of the translation.
Change 'schema' with 'modello' http://dizionari.corriere.it/dizionario_inglese/Inglese/B/blueprint.shtml
Change a passive action into an active one, as it sound more linear and direct.
Change 'di profili' with 'dei profili' as the plural of 'del' is 'dei'.
Change 'Gio' with more common 'Gi'.
Change 'vi' (pretty formal) with 'ci' which is more friendly and inline with the style of the rest of the strings.
Change 'URL' with 'Link' because int he text editor, link is more appropriate – URL sounds more technical and not comprehensive of the link text which is part of the outcome of the Link button.