Tracking issue for release 5

[sirhcel]

Bumping our MSRV is overdue. A fair amount of issues is waiting for it to get integrated. Let's sort what brings semver breaking changes and what requires a higher MSRV just for getting integrated. The milestone https://github.com/serialport/serialport-rs/milestone/1 does not make this distinction yet.

So let's get this planned at all and have a place for the discussions. Let's get started at all and update this issue as we go. Your Feedback and contributions are welcome.

Ideas:

• Switch from different platform-specific implementations of the TTYPort trait to a single struct (with platform specific implementations)
• Provive platform-specific functionality via extension traits

PRs to integrate bringing semver breaking changes:

• impl Sync for SerialPort trait #233
• Added support for 1.5 stop bits when reading current port settings #195

PRs requiring a higher MSRV for integration:

• feat: Add integration with schemars #264
• Upgrade nix to v0.30 #263

Current playgrounds:

• https://github.com/serialport/serialport-rs/tree/playground-5.0