test: add `.travis.yml` for testing on Travis CI

As discussed with @isaacs, build reports will be sent to #libuv IRC
channel. E-mail notifications are turned off so that Travis doesn't
bother committers about failures in forks.

.travis.yml

@@ -0,0 +1,14 @@
+language: node_js
+
+before_script:
+  - "./configure"
+  - "make"
+
+script:
+  - "make test"
+
+notifications:
+  email: false
+  irc:
+    - "irc.freenode.net#libuv"
+