New from v0.5.14 to v0.5.17:

• Replace most lungo and png icons by material icons (Honk2)
• Added chat search function (Honk2)
• Better UT media handling(nfsprodriver)
• Added UT image zoom function (sap-nocops)
• Show last message's author for each chat on main page (nfsprodriver)
• Several fixes (e.g. captions)