Allow commandline tests to use raw output

Introduce a new CLIGitCommand.rawExecute() helper that behaves
just like execute() except that instead of processing its output
it returns it raw.

So now you can do

	final byte[] expect = { 0, 1, 2, 3 };
	final byte[] actual = CLIGitCommand.rawExecute(
			"git show HEAD:goo.raw", db);
	assertArrayEquals(expect, actual);

to test the output from "git show HEAD:goo.raw" without being
distracted by encoding issues.

Noticed while writing tests for a new "jgit archive" command that
writes its output in ZIP format.

Change-Id: I2fe6020a537975d0ccf414b7125d85d6cd86898c

org.eclipse.jgit.pgm.test/src/org/eclipse/jgit/pgm/CLIGitCommand.java

@@ -70,6 +70,16 @@ public class CLIGitCommand {
 
 	public static List<String> execute(String str, Repository db)
 			throws Exception {
+		try {
+			return IO.readLines(new String(rawExecute(str, db)));
+		} catch (Die e) {
+			return IO.readLines(MessageFormat.format(CLIText.get().fatalError,
+					e.getMessage()));
+		}
+	}
+
+	public static byte[] rawExecute(String str, Repository db)
+			throws Exception {
 		String[] args = split(str);
 		if (!args[0].equalsIgnoreCase("git") || args.length < 2)
 			throw new IllegalArgumentException(
@@ -91,14 +101,11 @@ public class CLIGitCommand {
 		try {
 			cmd.execute(bean.getArguments().toArray(
 					new String[bean.getArguments().size()]));
-		} catch (Die e) {
-			return IO.readLines(MessageFormat.format(CLIText.get().fatalError,
-					e.getMessage()));
 		} finally {
 			if (cmd.outw != null)
 				cmd.outw.flush();
 		}
-		return IO.readLines(baos.toString());
+		return baos.toByteArray();
 	}
 
 	/**