Introduced configuration header for variant managment: At the moment several defines are distributed across the code allowing special SW builds (e.g. logging simulated dives). To make these options more transparent and easier to configurate a separate header has been added. With this header an new option for an optical pressure sensor was introduced.

Heinrichs Weikamp OSTC4 update files.

The builds are for testing purposes only. Be careful, they might not work and are definitely not recommended for real dives.