long overdue maintenance

contributions:

• improve general onewire-behavior and also ds2438 (#97, thanks to @raintonr)
• improve DELL-Charging-Example of ds2502 (#105, thanks to @rikka0w0)
• add ds2430 (#55, thanks to @Siarhei-Hanchuk)
• uncover onewire-flaw in search-rom (thanks to @Siarhei-Hanchuk)
• improve compatibility with SAMD21 (thanks to @sabas1080)

other changes:

• add ds2434 and probably 90% of ds2436
• remove datasheets (now in datasheet-branch) for quicker lib-updates
• add clang-format file
• spell-checking and file-formatting automated with pre-commit
• small bug-fix in ds2408
• fully implement DS2430