Auto merge of #15670 - nox:die-plugins-die, r=Manishearth

Kill the plugins crate and its clippy support

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components/constellation/Cargo.toml

@@ -26,7 +26,6 @@ log = "0.3.5"
 msg = {path = "../msg"}
 net_traits = {path = "../net_traits"}
 offscreen_gl_context = "0.6"
-plugins = {path = "../plugins"}
 profile_traits = {path = "../profile_traits"}
 script_traits = {path = "../script_traits"}
 serde = "0.9"

components/constellation/lib.rs

@@ -2,13 +2,10 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#![deny(unsafe_code)]
 #![feature(box_syntax)]
 #![feature(conservative_impl_trait)]
 #![feature(mpsc_select)]
-#![feature(plugin)]
-#![plugin(plugins)]
-
-#![deny(unsafe_code)]
 
 extern crate backtrace;
 extern crate bluetooth_traits;