plugin_framework, add event listening

Signed-off-by: fufesou <shuanglongchen@yeah.net>

src/plugin/desc.rs

@@ -60,6 +60,7 @@ pub struct Desc {
     github: String,
     location: Location,
     config: Config,
+    listen_events: Vec<String>,
 }
 
 impl Desc {
@@ -115,4 +116,8 @@ impl Desc {
     pub fn config(&self) -> &Config {
         &self.config
     }
+
+    pub fn listen_events(&self) -> &Vec<String> {
+        &self.listen_events
+    }
 }