Fix deprecation warnings for tr.

I switched over to the bit-vec/bit-set cargos.

deps/Cargo.toml

@@ -8,6 +8,8 @@ name = "null"
 [dependencies]
 libc = "0.1.8"
 getopts = "0.2.11"
+bit-vec = "0.3.0"
+bit-set = "0.2.0"
 num_cpus = "*"
 rand = "0.3.8"
 regex = "0.1.38"

src/tr/deps.mk

@@ -0,0 +1 @@
+DEPLIBS += bit-vec bit-set

src/tr/tr.rs

@@ -1,5 +1,5 @@
 #![crate_name = "tr"]
-#![feature(io)]
+#![feature(io, vecmap)]
 
 /*
  * This file is part of the uutils coreutils package.
@@ -12,10 +12,12 @@
  * file that was distributed with this source code.
  */
 
+extern crate bit_set;
 extern crate getopts;
 
+use bit_set::BitSet;
 use getopts::Options;
-use std::collections::{BitSet, VecMap};
+use std::collections::VecMap;
 use std::io::{stdin, stdout, BufReader, Read, Write};
 
 use expand::ExpandSet;