Vendor dependencies

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vendor/num_cpus/README.md

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+# num_cpus
+
+[![crates.io](https://img.shields.io/crates/v/num_cpus.svg)](https://crates.io/crates/num_cpus)
+[![Travis CI Status](https://travis-ci.org/seanmonstar/num_cpus.svg?branch=master)](https://travis-ci.org/seanmonstar/num_cpus)
+[![AppVeyor status](https://ci.appveyor.com/api/projects/status/qn8t6grhko5jwno6?svg=true)](https://ci.appveyor.com/project/seanmonstar/num-cpus)
+
+- [Documentation](https://docs.rs/num_cpus)
+- [CHANGELOG](CHANGELOG.md)
+
+Count the number of CPUs on the current machine.
+
+## Usage
+
+Add to Cargo.toml:
+
+```toml
+[dependencies]
+num_cpus = "1.0"
+```
+
+In your `main.rs` or `lib.rs`:
+
+```rust
+extern crate num_cpus;
+
+// count logical cores this process could try to use
+let num = num_cpus::get();
+```