Add Java based test runner

This is approximately a 10x speedup on the test suite including
compilation.

Test.java

@@ -0,0 +1,69 @@
+import rars.AssemblyException;
+import rars.SimulationException;
+import rars.api.Options;
+import rars.api.Program;
+import rars.simulator.Simulator;
+
+import java.io.File;
+
+public class Test {
+    public static void main(String[] args){
+        Options opt = new Options();
+        opt.startAtMain = true;
+        opt.maxSteps = 500;
+        Program p = new Program(opt);
+        File[] tests = new File("./test").listFiles(), riscv_tests = new File("./test/riscv-tests").listFiles();
+        if(tests == null){
+            System.out.println("./test doesn't exist");
+            return;
+        }
+        StringBuilder total = new StringBuilder("\n");
+        for(File test : tests){
+            if(test.isFile() && test.getName().endsWith(".s")){
+                String errors = run(test.getPath(),p);
+                if(errors.equals("")) {
+                    System.out.print('.');
+                }else{
+                    System.out.print('X');
+                    total.append(errors).append('\n');
+                }
+            }
+        }
+        if(riscv_tests == null){
+            System.out.println("./test/riscv-tests doesn't exist");
+            return;
+        }
+        for(File test : riscv_tests){
+            if(test.isFile() && test.getName().endsWith(".s")){
+                String errors = run(test.getPath(),p);
+                if(errors.equals("")) {
+                    System.out.print('.');
+                }else{
+                    System.out.print('X');
+                    total.append(errors).append('\n');
+                }
+            }
+        }
+        System.out.println(total);
+    }
+    public static String run(String path, Program p){
+        try {
+            p.assemble(path);
+            p.setup(null,"");
+            Simulator.Reason r = p.simulate();
+            if(r != Simulator.Reason.NORMAL_TERMINATION){
+                return "Ending abnormally while executing " + path;
+            }else{
+                if(p.getExitCode() == 42){
+                    return "";
+                }else{
+                    return "Final exit code was wrong for " + path;
+                }
+            }
+        } catch (AssemblyException ae){
+            return "Failed to assemble " + path;
+        } catch (SimulationException se){
+            return "Crashed while executing " + path;
+        }
+    }
+}

test.sh

@@ -1,16 +1,4 @@
 #!/bin/bash
-RUN="java -jar -ea ./rars.jar"
-ERRORS=""
-for f in ./test/*.s ./test/riscv-tests/*.s
-do	
-	$RUN $f > /dev/null
-	if [ $? -eq 42 ]
-	then 
-		printf "."
-	else
-		printf "X"	
-		ERRORS="$ERRORS\nFailure on file $f"
-	fi
-done
-
-printf "$ERRORS\n"
+javac -cp rars.jar Test.java
+java -cp rars.jar Test
+rm Test.class