curl timeout on one package cause the overall install fail

[grissiom]

I have a slow connection to the AWS so the curl is likely to fail to download the cargo. After the timeout, rustup-init will delete all the temp files so I've to start over and over again. Here is the log:

./rustup-init -v --no-modify-path

Welcome to Rust!

This will download and install the official compiler for the Rust programming 
language, and its package manager, Cargo.

It will add the cargo, rustc, rustup and other commands to Cargo's bin 
directory, located at:

  /home/grissiom/.cargo/bin

This path needs to be in your PATH environment variable, but will not be added 
automatically.

You can uninstall at any time with rustup self uninstall and these changes will
be reverted.

Current installation options:

   default host triple: x86_64-unknown-linux-gnu
     default toolchain: stable
  modify PATH variable: no

1) Proceed with installation (default)
2) Customize installation
3) Cancel installation
1

verbose: installing toolchain 'stable-x86_64-unknown-linux-gnu'
verbose: toolchain directory: '/home/grissiom/.rustup/toolchains/stable-x86_64-unknown-linux-gnu'
info: syncing channel updates for 'stable-x86_64-unknown-linux-gnu'
verbose: creating temp file: /home/grissiom/.rustup/tmp/_bmgbnllh3nsrjuj_file
verbose: downloading file from: 'https://static.rust-lang.org/dist/channel-rust-stable.toml.sha256'
verbose: downloading with curl
verbose: deleted temp file: /home/grissiom/.rustup/tmp/_bmgbnllh3nsrjuj_file
verbose: no update hash at: '/home/grissiom/.rustup/update-hashes/stable-x86_64-unknown-linux-gnu'
verbose: creating temp file: /home/grissiom/.rustup/tmp/z83ayr388cskczt4_file.toml
verbose: downloading file from: 'https://static.rust-lang.org/dist/channel-rust-stable.toml'
verbose: downloading with curl
verbose: checksum passed
verbose: deleted temp file: /home/grissiom/.rustup/tmp/z83ayr388cskczt4_file.toml
info: downloading component 'rustc'
verbose: creating temp file: /home/grissiom/.rustup/tmp/9vht9tz39xey6xnv_file
verbose: downloading file from: 'https://static.rust-lang.org/dist/2016-12-21/rustc-1.14.0-x86_64-unknown-linux-gnu.tar.gz'
verbose: downloading with curl
 47.1 MiB /  47.1 MiB (100 %) 220.8 KiB/s ETA:   0 s                
verbose: checksum passed
info: downloading component 'rust-std'
verbose: creating temp file: /home/grissiom/.rustup/tmp/0djwi0zdnpjhaoep_file
verbose: downloading file from: 'https://static.rust-lang.org/dist/2016-12-21/rust-std-1.14.0-x86_64-unknown-linux-gnu.tar.gz'
verbose: downloading with curl
 56.8 MiB /  56.8 MiB (100 %) 236.8 KiB/s ETA:   0 s                 
verbose: checksum passed
info: downloading component 'cargo'
verbose: creating temp file: /home/grissiom/.rustup/tmp/opwlmgc9qyatcy7z_file
verbose: downloading file from: 'https://s3.amazonaws.com/rust-lang-ci/cargo-builds/298a0127f703d4c2500bb06d309488b92ef84ae1/cargo-nightly-x86_64-unknown-linux-gnu.tar.gz'
verbose: downloading with curl
151.6 KiB /   4.0 MiB (  4 %)  13.4 KiB/s ETA: 294 s                verbose: deleted temp file: /home/grissiom/.rustup/tmp/9vht9tz39xey6xnv_file
verbose: deleted temp file: /home/grissiom/.rustup/tmp/0djwi0zdnpjhaoep_file
verbose: removing toolchain directory: '/home/grissiom/.rustup/toolchains/stable-x86_64-unknown-linux-gnu'
error: component download failed for cargo-x86_64-unknown-linux-gnu
info: caused by: could not download file from 'https://s3.amazonaws.com/rust-lang-ci/cargo-builds/298a0127f703d4c2500bb06d309488b92ef84ae1/cargo-nightly-x86_64-unknown-linux-gnu.tar.gz' to '/home/grissiom/.rustup/tmp/opwlmgc9qyatcy7z_file
info: caused by: error during download
info: caused by: [28] Timeout was reached (Operation too slow. Less than 10 bytes/sec transferred the last 30 seconds)

I think comment out the lines

            try!(handle.low_speed_limit(10).chain_err(|| "failed to set low speed limit"));
            try!(handle.low_speed_time(Duration::new(30, 0)).chain_err(|| "failed to set low speed time"));

in src/download/src/lib.rs will deal with the issue. Maybe we need them to be options?