Parametric Piano Hinge

2024-09-07: externalPianoHinge has the option to angle connections to other objects so now you can print hinges off the printbed

Wanted a hinge for future projects that has an easily customizable length and diameter.

If you're adding this to an OpenSCAD file, there's two ways you can use it:
- the normal pianoHinge module, which modifies its child object to have a hinge where you place it
- the externalPianoHinge module, which renders the hinge itself along with "bridges" that connect the hinge to the objects on either side

The .scad file has a demo of each function that should produce identical hinges, just use the function that best suits your situation if including this in your own design.