SWISS WATCHING Protestant church, with a modern Catholic counterpart nearby, the one hotel, a post office, a butcher, a baker (no candlestickmaker) and two of those aforementioned restau- rants. The other five must be hidden away in the backstreets. Down at the main road is one of the ubiquitous Wanderweg signs, but here it seems a little superfluous to be told that it's a four-and-half-hour walk back to Zurich. As tempting as that is, when the bus trundles into view exactly on time, we hop on. WELCOME TO HEIDILAND `I can't believe I'm finally standing in Heidi's house; it's like a dream come true.' Not my words but ones written by an enthusiastic American tourist in the visitors' book at the