GraphViz does not support the a HTML tag when generating the tables for the
cables/connectors, so this change will remove these tags for the graph generation.
However for the HTML BOM output table these links will be generated.
- Shorten `part_number` to `pn`
- Shorten `manufacturer_part_number` to `mpn`
- Show `manufacturer` and `mpn` in a single cell of the node
- Replace `manufacturer` with `'MPN'`within the node if no manufacturer is specified.
- Rearrange order of P/N fields within node
`{pn} | {manufacturer}: {mpn}`
