Represent serial numbers using SerialNumber struct

In a previous commit, we changed the serial number representation from a
string to an integer.  This made it easier to compare serial numbers,
but also introduced new problems:
- Serial numbers should be formatted consistently, for example as
  "{:#010x}".  It is hard to ensure this for an integer value.
- The format of the serial number may be subject to change.  Users
  should not rely too much on the u32 representation.

Therefore we introduce a new SerialNumber struct that represents a
serial number.  Currently it only stores a u32 value.  The following
traits and functions can be used to access its value:
- FromStr for string parsing
- ToString/Display for string formatting
- as_u32 to access the underlying integer value

1 files changed, 1 insertions, 1 deletions

diff --git a/examples/list-devices.rs b/examples/list-devices.rs
index 47fa054..0066f8c 100644
--- a/examples/list-devices.rs
+++ b/examples/list-devices.rs
@@ -17,7 +17,7 @@ fn main() -> Result<(), nitrokey::Error> {
             let model = device.get_model();
             let status = device.get_status()?;
             println!(
-                "{}\t{}\t{}\t\t\t{:08x}",
+                "{}\t{}\t{}\t\t\t{}",
                 device_info.path, model, status.firmware_version, status.serial_number
             );
         }