build+ci: Synchronize build and CI scripts with ndn-cxx/NFD

This commit also fixes a minor problem causing compilation warnings.

Change-Id: I0c04d58fe9df24f181947b9fde1346283402fc7b
diff --git a/.travis.yml b/.travis.yml
index 4614546..db62c24 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,16 +1,27 @@
-# For Ubuntu platform only
-
-sudo: true
-language: cpp
-os:
-  - linux
-compiler:
-  - gcc
+sudo: required
+language: generic
+env:
+  global:
+    - JOB_NAME=limited-build
+matrix:
+  include:
+    - os: linux
+      dist: trusty
+      env:
+        - CXX=g++
+        - NODE_LABELS="Linux Ubuntu Ubuntu-14.04"
+    - os: linux
+      dist: trusty
+      env:
+        - CXX=clang++
+        - NODE_LABELS="Linux Ubuntu Ubuntu-14.04"
+    - os: osx
+      env:
+        - CXX=clang++
+        - NODE_LABELS="OSX OSX-10.9"
 notifications:
   email:
     on_success: always
     on_failure: always
-env:
-  - NODE_LABELS="Linux Ubuntu Ubuntu-12.04"
 script:
   - ./.jenkins