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

Kill the plugins crate and its clippy support

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ports/cef/Cargo.toml

@@ -28,7 +28,6 @@ libservo = {path = "../../components/servo"}
 log = {version = "0.3.5", features = ["release_max_level_info"]}
 msg = {path = "../../components/msg"}
 net_traits = {path = "../../components/net_traits"}
-plugins = {path = "../../components/plugins"}
 script_traits = {path = "../../components/script_traits"}
 servo_config = {path = "../../components/config"}
 servo_geometry = {path = "../../components/geometry"}

ports/cef/lib.rs

@@ -2,14 +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/. */
 
+#![allow(non_camel_case_types)]
 #![feature(box_syntax)]
 #![feature(core_intrinsics)]
 #![feature(link_args)]
-#![feature(plugin)]
-
-#![allow(non_camel_case_types)]
-
-#![plugin(plugins)]
 
 #[macro_use]
 extern crate log;

ports/servo/Cargo.toml

@@ -32,7 +32,6 @@ max_log_level = ["log/release_max_level_info"]
 webdriver = ["libservo/webdriver_server"]
 energy-profiling = ["libservo/energy-profiling"]
 testing = ["libservo/testing"]
-clippy = ["libservo/clippy"]
 debugmozjs = ["libservo/debugmozjs"]
 
 [dependencies]