Minor bug and typing fix

The @cache decorator as used in thread.py and fastener.py interfered with IDE type hints as discovered by user marked23 on the CadQuery discord group - thank you - and has been disabled.

A fix was made to internal TrapezoidalThread radii.

Threads

The 0.4.0 release introduces a new thread sub-package with classes for:

• IsoThread ISO Standard 60° threads found on most fasteners
• AcmeThread Acme 29° threads found on imperial machine equipment
• MetricTrapezoidalThread Metric Trapezoidal 30° thread found on metric machine equipment
  in addition to a base Thread that is used to make the above threads or custom threads. All of the threads have custom ends that can be one of four types: raw, fade, square or chamfer.

The fastener sub-package also gets the new method fastener_quantities() that provides the information needed for a bill-of-materials (i.e. fastener types and quantities) from the fasteners' assembly.

Note that this release requires python 3.9.

Fastener Expansion

This release is a major re-work of the fastener package. A large number of standardized fasteners are provided, as follows:
Nut

• DomedCapNut: din1587
• HexNut: iso4033, iso4035, iso4032
• HexNutWithFlange: din1665
• UnchamferedHexagonNut: iso4036
• SquareNut: din557

Screw

• ButtonHeadScrew: iso7380_1
• ButtonHeadWithCollarScrew: iso7380_2
• CheeseHeadScrew: iso14580, iso7048, iso1207
• CounterSunkScrew: iso2009, iso14582, iso14581, iso10642, iso7046
• HexHeadScrew: iso4017, din931, iso4014
• HexHeadWithFlangeScrew: din1662, din1665
• PanHeadScrew: asme_b_18.6.3, iso1580, iso14583
• PanHeadWithCollarScrew: din967
• RaisedCheeseHeadScrew: iso7045
• RaisedCounterSunkOvalHeadScrew: iso2010, iso7047, iso14584
• SetScrew: iso4026
• SocketHeadCapScrew: iso4762, asme_b18.3

Washer

• PlainWasher: iso7094, iso7093, iso7089, iso7091
• ChamferedWasher: iso7090
• CheeseHeadWasher: iso7092

In addition to the new fasteners, the following three new Workplane hole building methods are provided to simplify creation of appropriate holes into your parts for the above fasteners:

• clearanceHole,
• tapHole, and
• threadedHole.

These three methods can optionally place fasteners into an Assembly in the correct positions.

Literal nuts and bolts

Add a fastener sub-package to cq_warehouse which includes several type of parametric threads, nuts and screws/bolts.

Initial Release

First release of cq_warehouse including the following sub-packages:

• sprocket
• chain
• drafting
• extensions