cargo-edit 0.3.0-alpha.1

This extends Cargo to allow you to add and remove dependencies by modifying your `Cargo.toml` file from the command line. It contains `cargo add`, `cargo rm`, and `cargo upgrade`.

# Appveyor config originally copied from https://github.com/seanmonstar/reqwest
#
# appveyor-retry makes us more resilient to random network failures.
environment:
  matrix:
  - TARGET: x86_64-pc-windows-msvc
  - TARGET: i686-pc-windows-msvc
  - TARGET: x86_64-pc-windows-gnu
  - TARGET: i686-pc-windows-gnu
install:
  - appveyor-retry curl -sSf -o rustup-init.exe https://win.rustup.rs/
  - appveyor-retry rustup-init.exe -y --default-host %TARGET%
  - set PATH=%PATH%;C:\Users\appveyor\.cargo\bin
  - rustc -vV
  - cargo -vV
build: false
test_script:
  - appveyor-retry cargo build --verbose
  - cargo test --verbose
branches:
  except:
  - staging.tmp