mains tests can include any code

not wrapping as main anymore
(must still include mains)
first part of #11

test/mains/source/add__4.rb

@@ -1 +1,5 @@
-return 2 +2
+class Space
+  def main(arg)
+    return 2 +2
+  end
+end

test/mains/source/adds__10.rb

@@ -1,7 +1,11 @@
-a = 0
-b = 20
-while( a < b )
-  a = a + 1
-  b = b - 1
+class Space
+  def main(arg)
+    a = 0
+    b = 20
+    while( a < b )
+      a = a + 1
+      b = b - 1
+    end
+    return a
+  end
 end
-return a

test/mains/source/fibo__8.rb

@@ -1,11 +1,15 @@
-n = 6
-a = 0
-b = 1
-i = 1
-while( i < n )
-  result = a + b
-  a = b
-  b = result
-  i = i + 1
+class Space
+  def main(arg)
+    n = 6
+    a = 0
+    b = 1
+    i = 1
+    while( i < n )
+      result = a + b
+      a = b
+      b = result
+      i = i + 1
+    end
+    return result
+  end
 end
-return result

test/mains/source/puts_Hello-there_11.rb

@@ -1 +1,5 @@
-return "Hello-there".putstring
+class Space
+  def main(arg)
+    return "Hello-there".putstring
+  end
+end

test/mains/source/subs__0.rb

@@ -1,5 +1,9 @@
-b = 10
-while( b >= 1 )
-  b = b - 1
+class Space
+  def main(arg)
+    b = 10
+    while( b >= 1 )
+      b = b - 1
+    end
+    return b
+  end
 end
-return b