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

Kill the plugins crate and its clippy support

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components/gfx/Cargo.toml

@@ -27,7 +27,6 @@ log = "0.3.5"
 msg = {path = "../msg"}
 net_traits = {path = "../net_traits"}
 ordered-float = "0.4"
-plugins = {path = "../plugins"}
 range = {path = "../range"}
 serde = "0.9"
 serde_derive = "0.9"

components/gfx/lib.rs

@@ -8,12 +8,9 @@
 
 #![cfg_attr(any(target_os = "linux", target_os = "android"), feature(alloc))]
 #![feature(box_syntax)]
-#![feature(plugin)]
 #![feature(range_contains)]
 #![feature(unique)]
 
-#![plugin(plugins)]
-
 #![deny(unsafe_code)]
 
 #[cfg(any(target_os = "linux", target_os = "android"))]