Run master branch tests on Travis CI for the badge

Only run for Rust stable and the Linux target.

Author: dwijnand

.travis.yml

@@ -10,7 +10,7 @@ matrix:
   include:
     - env: TARGET=x86_64-unknown-linux-gnu
            ALT=i686-unknown-linux-gnu
-      if: branch != master OR type = pull_request
+
     - env: TARGET=x86_64-apple-darwin
            ALT=i686-apple-darwin
       os: osx

README.md

@@ -6,7 +6,7 @@ Learn more at https://doc.rust-lang.org/cargo/
 
 ## Code Status
 
-[![Build Status](https://travis-ci.com/rust-lang/cargo.svg?branch=auto-cargo)](https://travis-ci.com/rust-lang/cargo)
+[![Build Status](https://travis-ci.com/rust-lang/cargo.svg?branch=master)](https://travis-ci.com/rust-lang/cargo)
 [![Build Status](https://ci.appveyor.com/api/projects/status/github/rust-lang/cargo?branch=master&svg=true)](https://ci.appveyor.com/project/rust-lang-libs/cargo)
 
 Code documentation: https://docs.rs/cargo/