Second try at Travis+Cargo fixes

.travis.yml

@@ -6,5 +6,6 @@ install:
   - sudo apt-get install rust-nightly cargo
 script:
   - cargo build
-  - cargo test
+  - rustc --test src/exa -o exa-test
+  - ./exa-test
 

README.md

@@ -3,7 +3,7 @@ exa
 
 exa is a replacement for `ls` written in Rust.
 
-![Build status](https://travis-ci.org/ogham/exa.svg?branch=master)
+[![Build status](https://travis-ci.org/ogham/exa.svg)](https://travis-ci.org/ogham/exa)
 
 Screenshot
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