Raising Errno::ENOENT exception with a particular path instead of src, which may be an array.

Closes #59

lib/fakefs/fileutils.rb

@@ -102,7 +102,7 @@ module FakeFS
           FileSystem.add(dest_path, target.entry.clone)
           FileSystem.delete(path)
         else
-          raise Errno::ENOENT, src
+          raise Errno::ENOENT, path
         end
       end
     end

test/fakefs_test.rb

@@ -568,7 +568,6 @@ class FakeFSTest < Test::Unit::TestCase
     assert_equal ['/path', '/path/bar', '/path/bar/baz', '/path/bar2', '/path/bar2/baz', '/path/foo', '/path/foobar'], Dir['/**/*']
 
     assert_equal ['/path/bar', '/path/bar/baz', '/path/bar2', '/path/bar2/baz', '/path/foo', '/path/foobar'], Dir['/path/**/*']
-
     assert_equal ['/path/bar/baz'], Dir['/path/bar/**/*']
 
     FileUtils.cp_r '/path', '/otherpath'
@@ -803,6 +802,10 @@ class FakeFSTest < Test::Unit::TestCase
     assert_raise(Errno::ENOENT) do
       FileUtils.mv 'blafgag', 'foo'
     end
+    exception = assert_raise(Errno::ENOENT) do
+      FileUtils.mv ['foo', 'bar'], 'destdir'
+    end
+    assert_equal "No such file or directory - foo", exception.message
   end
 
   def test_mv_actually_works