Opening times malformed on upload

[mjray]

Line 819 of AndroidApp/CityZenApp/app/src/main/java/com/cityzen/cityzen/Fragments/EditPoiFragment.java puts a colon (":") between opening and closing times instead of a dash ("-") which appears contrary to https://wiki.openstreetmap.org/wiki/Key:opening_hours/specification and results in other apps being unable to interpret the uploaded data.