KLC pin numbering guidelines got lost

[poeschlr]

See KiCad/kicad-symbols#2095 (comment)

The rule would go something like this:

By default pin numbering follows the number as suggested for the package in industry standards or within the datasheet.

Exceptions are allowed if the package is highly specialized to the part at hand in which case a numbering scheme allowing the use of generic symbols is allowed.

We would then list the exceptions and the numbering scheme we decided to use. I am aware of:

• Audio connectors
• SD card holders
• In future Relays and buttons/switches (not yet fully decided but quite likely the numbering as in the european standard. ie A1,A2 for coil and x1 (x3), x2, x4 for contacts)

[poeschlr]

For audio connectors see: #364

[poeschlr]

Relays: #430