Update to jemallocator 0.5

Author: dtolnay

Cargo.toml

@@ -7,7 +7,7 @@ publish = false
 
 [dependencies]
 getopts = "0.2"
-jemallocator = "0.3"
+jemallocator = "0.5"
 json = { version = "0.12", optional = true }
 rustc-serialize = { version = "0.3", optional = true }
 serde = { version = "1.0", features = ["derive"], optional = true }