Parametric Ping Pong Paddle

A parametric ping pong paddle (or table tennis racket) with support for many different handle styles and blade shapes.

The example STL was generated with the following options:

```
handle_length = 100;
handle_style = "flared";
handle_thickness = 30;
handle_width = 45;
handle_offset = 10;

blade_width = 150;
blade_length = 160;
blade_thickness = 6;
blade_shape = "oblong";
blade_texture = "smooth";
```