Refactor mavlink-dump. Change from [[bin]] to [[example]].

Splitting the example has the following benefits:
- Faster normal compilation for library use
- Easier to retain compilation incremental files (faster re-compilation times)
- Cleaner library src/ directory
- no_std/std definitions and imports can be removed from the mavlink-dump example
- Executable name changes from mavlink -> mavlink-dump. More precise to locate and guess what it is for

Disadvantage:
- Installation time for the example is increased, but it is something rarely done

Cargo.toml

@@ -19,8 +19,9 @@ proc-macro2 = "1.0.43"
 lazy_static = "1.2.0"
 serde = { version = "1.0.115", optional = true, features = ["derive"] }
 
-[[bin]]
+[[example]]
 name = "mavlink-dump"
+path = "examples/mavlink-dump/src/main.rs"
 required-features = ["ardupilotmega"]
 
 [dependencies]

examples/mavlink-dump/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "mavlink-dump"
+authors = [
+    "Patrick José Pereira <[email protected]>",
+]
+license = "MIT/Apache-2.0"
+edition = "2018"
+version = "0.1.0"
+
+[profile.release]
+opt-level = 3
+lto = true # Performs "fat" LTO which attempts to perform optimizations across all crates within the dependency graph
+
+[dependencies.mavlink] # MAVLink library
+path = "../../"

src/bin/mavlink-dump.rs → examples/mavlink-dump/src/main.rs

@@ -1,11 +1,6 @@
 use mavlink::error::MessageReadError;
-#[cfg(feature = "std")]
 use std::{env, sync::Arc, thread, time::Duration};
 
-#[cfg(not(feature = "std"))]
-fn main() {}
-
-#[cfg(feature = "std")]
 fn main() {
     let args: Vec<_> = env::args().collect();
 
@@ -65,7 +60,6 @@ fn main() {
 }
 
 /// Create a heartbeat message using 'ardupilotmega' dialect
-#[cfg(feature = "std")]
 pub fn heartbeat_message() -> mavlink::ardupilotmega::MavMessage {
     mavlink::ardupilotmega::MavMessage::HEARTBEAT(mavlink::ardupilotmega::HEARTBEAT_DATA {
         custom_mode: 0,
@@ -78,7 +72,6 @@ pub fn heartbeat_message() -> mavlink::ardupilotmega::MavMessage {
 }
 
 /// Create a message requesting the parameters list
-#[cfg(feature = "std")]
 pub fn request_parameters() -> mavlink::ardupilotmega::MavMessage {
     mavlink::ardupilotmega::MavMessage::PARAM_REQUEST_LIST(
         mavlink::ardupilotmega::PARAM_REQUEST_LIST_DATA {
@@ -89,7 +82,6 @@ pub fn request_parameters() -> mavlink::ardupilotmega::MavMessage {
 }
 
 /// Create a message enabling data streaming
-#[cfg(feature = "std")]
 pub fn request_stream() -> mavlink::ardupilotmega::MavMessage {
     mavlink::ardupilotmega::MavMessage::REQUEST_DATA_STREAM(
         mavlink::ardupilotmega::REQUEST_DATA_STREAM_DATA {