extend selection of DIN41612 connectors

This selection was generated by an updated script using the kicad-footprint-generator. This current selection was built by checking the catalogs of ept, ERNI and Harting and collect the most standard series. Added in this commit were: B (was already present), C, D, E, F, Q, R Still missing standard series are:

• H11, H15 (vertical and horizontal are different from each other and require an updated script, only H11 horizontal is present)
• M (has a lot of variations which needs to be tracked). There are also many manufacturer specific variants which might follow (some are very easy to add to the script, others not so much).

The new script was made to copy the style of the existing scripts, just adding the increased flexiblity to generate all series. Changes to the generated footprints compared to the existing B series are:

• a1 pin is a roundrect instead of rect
• vertical connectors got their silk ref moved to the side. They are often used on backplanes, so there might be no space on top.
• courtyard of the horizontal connector is simpler on the connector side. This space if off the PCB anyways and there needs to be room to attach the connector.
• names are now always using two digit numbers for rows and pins.
• Q and R series vertical have slightly more drawings, trying to symbolise their inverted connector nature (vertical is male, while usually they are female).

There are two series where the names contain the rows which are occupied. These are due to connectors only ept sells (E and F series 2x16). The standard is to leave the center row empty, ept also sells a variant where the top row is empty. To distinguish those only the non-standard has the rows added to the name.

As a general remark to these connectors. The naming of the pins and rows is very strict, based on the location relative to the mounting position. At least in vertical this always holds true, horizontal got some flexibility on the spacing. The origin is always located at the a1 pin, even if it is not present. This ensures that connectors can be switched without having to change everything. This was already the case for the existing connectors.

There are no real datasheets (as far as I could see the standard is not public). I worked of the catalogs of Harting, ERNI and ept. Some example screenshots below, but there are way to many connectors to display them all. The generation script can be found here, I will post a PR once it is clear that the style is fine.