Clarify help text

src/main/java/CommandLineInterface.java

@@ -234,7 +234,7 @@ public class CommandLineInterface {
                 .desc("Matches CDR3s. Requires a graph/data file.")
                 .build();
         Option printVersion = Option.builder("version")
-                .desc("Print the version number").build();
+                .desc("Prints the program version number to stdout").build();
         OptionGroup mainGroup = new OptionGroup();
         mainGroup.addOption(help);
         mainGroup.addOption(printVersion);