Update Matrix4x4.as

var m:Matrix4x4 = new Matrix4x4();
trace('translationX=' + m.translationX); // 0
m.appendTranslation(1);
trace('translationX=' + m.translationX); // 0
Update Matrix4x4.as

correct Translation
Merge pull request #127 from MerlinTwi/patch-2

Update Matrix4x4.as