Add analog example to README about netlistsvg

[amstan]

We should probably have the nice class A amplifier, though, would be nice if it didn't have that redundant base connection.

Also how about a regulator circuit?

regulator.json

{
	modules: {
		undefined: {
			cells: {
				C1: {
					type: "c_v",
					connections: {
						A: [
							1
						],
						B: [
							2
						]
					}
				},
				VIN: {
					type: "vcc",
					attributes: {
						value: "VIN"
					},
					connections: {
						A: [
							1
						]
					}
				},
				GNDC1: {
					type: "gnd",
					connections: {
						A: [
							2
						]
					}
				},
				U1: {
					type: "U1 (LM317)",
					port_directions: {
						IN: "input",
						ADJ: "output",
						OUT: "output"
					},
					connections: {
						IN: [
							1
						],
						OUT: [
							3
						],
						ADJ: [
							5
						]
					}
				},
				VOUT: {
					type: "vcc",
					attributes: {
						value: "VOUT"
					},
					connections: {
						A: [
							3
						]
					}
				},
				C2: {
					type: "c_v",
					connections: {
						A: [
							3
						],
						B: [
							4
						]
					}
				},
				GNDC2: {
					type: "gnd",
					connections: {
						A: [
							4
						]
					}
				},
				R1: {
					type: "r_v",
					connections: {
						A: [
							3
						],
						B: [
							5
						]
					}
				},
				R2: {
					type: "r_v",
					connections: {
						A: [
							5
						],
						B: [
							6
						]
					}
				},
				GNDR2: {
					type: "gnd",
					connections: {
						A: [
							6
						]
					}
				}
			}
		}
	}
}