Actually allow setting of truce

src/main/java/com/massivecraft/factions/cmd/CmdRelationTruce.java

@@ -0,0 +1,11 @@
+package com.massivecraft.factions.cmd;
+
+import com.massivecraft.factions.struct.Relation;
+
+public class CmdRelationTruce extends FRelationCommand {
+
+    public CmdRelationTruce() {
+        aliases.add("truce");
+        targetRelation = Relation.TRUCE;
+    }
+}