MTU and Netlink update (DefGuard#63)

* Handle MTU

* Derive Copy for IpVersion

* Set MTU

* Fix MTU as u32

* Fix Linux test

* Update netlink-packet-route to 0.20

* Fix CIDR parsing; test network interface assignment; cleanups

* Flush IP addresses on Linux

* Fix netlink::flush_addresses

* Fix build for FreeBSD

* bump version

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Co-authored-by: Aleksander <[email protected]>

chore: Bump version 0.4.4 -> 0.4.5 (DefGuard#62)

chore: bump version v0.4.4

feat: allow domain name as endpoint address (DefGuard#54)

* Add dns resolution for peer endpoint
* Handle both domain and IP endpoint
* chore: bump version
* Markdown links in function docstrings
* Leave IP resolution to `to_socket_addr()` function

chore: bump version

Tracing crashes (DefGuard#52)

* Key can be converted from base16 string; other debugging improvements

* Format and update Cargo.lock

* Remove unused code

* Rename KernelNotSupported to PlatformNotSupported

* Revert KernelNotSupported

* Bump version

chore: bump version to 0.4 (DefGuard#48)

* bump version

* bump CI image version

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Co-authored-by: Maciej Wójcik <[email protected]>

fix: hide private keys in logs (DefGuard#42)

* add manual `Debug` implementations to hide private keys

* update dependencies

* bump version

* update server example

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Co-authored-by: Maciej Wójcik <[email protected]>

chore: bump version to 0.3.1

fix: FreeBSD kld_load() (DefGuard#35)