We use IN for INCH as units, but IN is defined in a Windows header
(cherry picked from commit b0fe4df3c565027801cbbac56c6ee0da254bd74a)
(cherry picked from commit 0acdabd1eb1a2d5ab9b6aa9f71df31c8cf088de8)
(cherry picked from commit eaa1e6d59464e8356d24afd1d29148335010f67a)
Recommendation is to avoid using the year nomenclature as this
information is already encoded in the git repo. Avoids needing to
repeatly update.
Also updates AUTHORS.txt from current repo with contributor names
To represent KiCad's internal units (1 nm), it's enough to have:
- 6 decimal digits in mm;
- 8 decimal digits in inches.
There's not much point in reducing the precision.
Up to 10 digits allowed just in case.
Also changes precision to 6 decimal digits by default.
