Update to current rust

schala-repl/Cargo.toml

@@ -7,7 +7,7 @@ edition = "2018"
 [dependencies]
 llvm-sys = "70.0.2"
 take_mut = "0.2.2"
-itertools = "0.5.8"
+itertools = "0.10"
 getopts = "0.2.18"
 lazy_static = "0.2.8"
 maplit = "*"

schala-repl/src/lib.rs

@@ -1,5 +1,4 @@
-#![feature(link_args)]
-#![feature(slice_patterns, box_patterns, box_syntax, proc_macro_hygiene, decl_macro)]
+#![feature(box_patterns, box_syntax, proc_macro_hygiene, decl_macro)]
 #![feature(plugin)]
 extern crate getopts;
 extern crate linefeed;

schala-repl/src/repl/directive_actions.rs

@@ -1,7 +1,6 @@
 use super::{Repl, InterpreterDirectiveOutput};
 use crate::repl::help::help;
 use crate::language::{LangMetaRequest, LangMetaResponse, DebugAsk, DebugResponse}; 
-use itertools::Itertools;
 use std::fmt::Write as FmtWrite;
 
 #[derive(Debug, Clone)]