Did move to superview

Modified class a little bit and renamed so it to look more familiar to others.

- now view disappears after it was added as subview to superview
- disappear animation based on changing view's alpha to 0
- added property for view's disappear animation duration (default is 2 sec, for custom time - needs to be modified before adding to superview)
- renamed files and class to look like traditional view class name
- readme edited due to new class name