Add Travis CI hook and build status.

.travis.yml

@@ -0,0 +1,8 @@
+language: erlang
+notifications:
+  email: eng@basho.com
+otp_release:
+  - R15B01
+  - R15B
+  - R14B04
+  - R14B03

README.org

@@ -4,7 +4,9 @@
   that plays nicely with traditional UNIX logging tools like logrotate and
   syslog.
 
-*  Features
+  [[https://travis-ci.org/basho/lager][https://secure.travis-ci.org/basho/lager.png]]
+
+* Features
     - Finer grained log levels (debug, info, notice, warning, error, critical,
       alert, emergency)
     - Logger calls are transformed using a parse transform to allow capturing