make deps
make release

I got this error:

relx -o rel/etorrent
make: relx：command not found
make: *** [release] error 127

erlang:
Erlang R16B03-1 (erts-5.10.4) [source] [64-bit] [smp:4:4] [async-threads:10] [hipe] [kernel-poll:false]

Eshell V5.10.4 (abort with ^G)

I try to download relx from:
https://github.com/erlware/relx/releases/download/v0.5.2/relx
and put it into etorrent dir,and compile again,I got another error:

===> Starting relx build process ...
===> Resolving OTP Applications from directories:
/work/erlang/etorrent/deps
/usr/lib/erlang/lib
===> Resolving available OTP Releases from directories:
/work/erlang/etorrent/deps
/usr/lib/erlang/lib
===> Resolved etorrent-1.2.1
Errors generating release
Duplicated application included:
ets_lru included in idna and hackney

make: *** [release] 错误 127