Moved plugin API to Uid instead of usize for entity IDs, hello plugin to an example

plugin/rt/Cargo.toml

@@ -9,3 +9,10 @@ plugin-api = { package = "veloren-plugin-api", path = "../api" }
 plugin-derive = { package = "veloren-plugin-derive", path = "../derive"}
 serde = {version = "1.0.118", features = ["derive"]}
 bincode = "1.3.1"
+
+[[example]]
+name = "hello"
+crate-type = ["cdylib"]
+
+[dev-dependencies]
+plugin-derive = { package = "veloren-plugin-derive", path = "../derive"}

plugin/rt/examples/hello.rs

@@ -0,0 +1,34 @@
+use veloren_plugin_rt::{
+    api::{event::*, Action, GameMode},
+    *,
+};
+
+#[veloren_plugin_rt::event_handler]
+pub fn on_load(load: PluginLoadEvent) {
+    match load.game_mode {
+        GameMode::Server => emit_action(Action::Print("Hello, server!".to_owned())),
+        GameMode::Client => emit_action(Action::Print("Hello, client!".to_owned())),
+        GameMode::Singleplayer => emit_action(Action::Print("Hello, singleplayer!".to_owned())),
+    }
+}
+
+#[event_handler]
+pub fn on_command_testplugin(command: ChatCommandEvent) -> Result<Vec<String>, String> {
+    Ok(vec![format!(
+        "Player of id {:?} sended command with args {:?}",
+        command.player, command.command_args
+    )])
+}
+
+#[event_handler]
+pub fn on_player_join(input: PlayerJoinEvent) -> PlayerJoinResult {
+    emit_action(Action::PlayerSendMessage(
+        input.player_id,
+        format!("Welcome {} on our server", input.player_name),
+    ));
+    if input.player_name == "Cheater123" {
+        PlayerJoinResult::CloseConnection
+    } else {
+        PlayerJoinResult::None
+    }
+}