Allow easy custom candidate sorting

reader/src/main/java/org/jline/reader/Candidate.java

@@ -24,14 +24,15 @@ public class Candidate implements Comparable<Candidate> {
     private final String suffix;
     private final String key;
     private final boolean complete;
+    private final int sort;
 
     /**
      * Simple constructor with only a single String as an argument.
      *
      * @param value the candidate
      */
     public Candidate(String value) {
-        this(value, value, null, null, null, null, true);
+        this(value, value, null, null, null, null, true, 0);
     }
 
     /**
@@ -44,15 +45,32 @@ public Candidate(String value) {
      * @param suffix the suffix
      * @param key the key
      * @param complete the complete flag
+     * @param sort the sort flag
      */
-    public Candidate(String value, String displ, String group, String descr, String suffix, String key, boolean complete) {
+    public Candidate(String value, String displ, String group, String descr, String suffix, String key, boolean complete, int sort) {
         this.value = Objects.requireNonNull(value);
         this.displ = Objects.requireNonNull(displ);
         this.group = group;
         this.descr = descr;
         this.suffix = suffix;
         this.key = key;
         this.complete = complete;
+        this.sort = sort;
+    }
+
+    /**
+     * Constructs a new Candidate.
+     *
+     * @param value the value
+     * @param displ the display string
+     * @param group the group
+     * @param descr the description
+     * @param suffix the suffix
+     * @param key the key
+     * @param complete the complete flag
+     */
+    public Candidate(String value, String displ, String group, String descr, String suffix, String key, boolean complete) {
+    	this(value, displ, group, descr, suffix, key, complete, 0);
     }
 
     /**
@@ -133,9 +151,23 @@ public boolean complete() {
         return complete;
     }
 
+    /**
+     * Integer used to override default sort logic. 
+     * @return the sort int
+     */
+    public int sort() {
+        return sort;
+    }
+
+
     @Override
     public int compareTo(Candidate o) {
-        return value.compareTo(o.value);
+    	// If both candidates have same sort, use default behavior
+    	if( sort == o.sort() ) {
+            return value.compareTo(o.value);
+    	} else {
+    		return sort - o.sort();
+    	}
     }
 
     @Override