LnSensorManager deprecation of one sensor numbering format (#7377)

Deprecate LocoNetSensorManager's partial support for createSensorName("3:15","L") where "3:15" is supposed to mean "board 3, bit 15", and which returns the equivalent sensor system name of "LS47".  

Logs a one-time (per JMRI session) warning to the System Console log stating that the format is deprecated and support will be removed at a future date.

java/src/jmri/jmrix/loconet/LnSensorManager.java

@@ -3,6 +3,7 @@
 import java.util.Locale;
 import jmri.JmriException;
 import jmri.Sensor;
+import jmri.util.Log4JUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -135,6 +136,12 @@ public boolean allowMultipleAdditions(String systemName) {
     @Override
     public String createSystemName(String curAddress, String prefix) throws JmriException {
         if (curAddress.contains(":")) {
+
+            // NOTE: This format is deprecated in JMRI 4.17.4 on account the 
+            // "byte:bit" format cannot be used under normal JMRI usage 
+            // circumstances.  It is retained for the normal deprecation period 
+            // in order to support any atypical usage patterns.
+
             int board = 0;
             int channel = 0;
             // Address format passed is in the form of board:channel or T:turnout address
@@ -161,6 +168,9 @@ public String createSystemName(String curAddress, String prefix) throws JmriExce
             } else {
                 iName = 16 * board + channel - 16;
             }
+            jmri.util.Log4JUtil.warnOnce(log, 
+                    "LnSensorManager.createSystemName(curAddress, prefix) support for curAddress using the '{}' format is deprecated as of JMRI 4.17.4 and will be removed in a future JMRI release.  Use the curAddress format '{}' instead.",
+                    curAddress, iName);
         } else {
             // Entered in using the old format
             try {

java/test/jmri/jmrix/loconet/LnSensorManagerTest.java

@@ -91,6 +91,21 @@ public void testAsAbstractFactory() {
 
     }
 
+    @Test
+    public void testDeprecationWarningSensorNumberFormat() {
+        boolean excep= false;
+        String s = "";
+        try {
+            s = l.createSystemName("3:5", "L");
+        } catch (jmri.JmriException e) {
+            excep = true;
+        }
+        Assert.assertEquals("no exception during createSystemName for arguments '3:5', 'L'", false, excep);
+        Assert.assertEquals("check createSystemName for arguments '3:5', 'L'", "LS37", s);
+        jmri.util.JUnitAppender.assertWarnMessage(
+                "LnSensorManager.createSystemName(curAddress, prefix) support for curAddress using the '3:5' format is deprecated as of JMRI 4.17.4 and will be removed in a future JMRI release.  Use the curAddress format '37' instead.");
+    }
+
     // The minimal setup for log4J
     @Override
     @Before
@@ -115,5 +130,5 @@ public void tearDown() {
     }
 
     private final static Logger log = LoggerFactory.getLogger(LnSensorManagerTest.class);
-    
+
 }