TACS support (variations added to AMPS code)

These are:

- Bandwidth only 25 KHz, so lower deviations
- Data rate only 8000 KHz
- SID is called AID (Area ID)
- MIN1 coding is different

src/amps/stations.c

@@ -1,6 +1,17 @@
 #include <stdio.h>
+#include <string.h>
 #include "stations.h"
 
+void numbering(const char *number, const char __attribute__((unused)) **carrier, const char **country, const char **national_number)
+{
+	static char digits[64];
+
+	*country = "USA";
+	strcpy(digits, "1");
+	strcat(digits, number);
+	*national_number = number;
+}
+
 /*
 	1: the SID, system Identification number
 	2: the BID, the billing identification number, or 0= if same as the SID