Add Travis CI

.travis.yml

+language: generic
+addons:
+  apt:
+    packages:
+      - libc6:i386
+      - libstdc++6:i386
+env:
+  global:
+    - IDE_VERSION=1.6.12
+before_install:
+  - /sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_1.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :1 -ac -screen 0 1280x1024x16
+  - sleep 3
+  - export DISPLAY=:1.0
+  - wget http://downloads.arduino.cc/arduino-$IDE_VERSION-linux64.tar.xz
+  - tar xf arduino-$IDE_VERSION-linux64.tar.xz
+  - mv arduino-$IDE_VERSION $HOME/arduino-ide
+  - export PATH=$PATH:$HOME/arduino-ide
+  - arduino --pref "boardsmanager.additional.urls=https://sandeepmistry.github.io/arduino-nRF5/package_nRF5_boards_index.json" --install-boards sandeepmistry:nRF5
+  - buildExampleSketch() { arduino --verbose-build --verify --board $1 $HOME/arduino-ide/examples/$2/$3/$3.ino; }
+install:
+  - mkdir -p $HOME/Arduino/hardware/sandeepmistry
+  - ln -s $PWD $HOME/Arduino/hardware/sandeepmistry/.
+script:
+  - buildExampleSketch sandeepmistry:nRF5:nRF52DK 01.Basics Blink
+  - buildExampleSketch sandeepmistry:nRF5:BluzDK 01.Basics Blink
+  - buildExampleSketch sandeepmistry:nRF5:BLENano:version=1_0 01.Basics Blink
+  - buildExampleSketch sandeepmistry:nRF5:RedBearLab_nRF51822:version=1_0 01.Basics Blink
+  - buildExampleSketch sandeepmistry:nRF5:BBCmicrobit 01.Basics Blink
+  - buildExampleSketch sandeepmistry:nRF5:Generic_nRF51822:chip=xxac 01.Basics Blink
+  - buildExampleSketch sandeepmistry:nRF5:OSHChip 01.Basics Blink

README.md

 # Arduino Core for Nordic Semiconductor nRF5 based boards
 
+[![Build Status](https://travis-ci.org/sandeepmistry/arduino-nRF5.svg?branch=master)](https://travis-ci.org/sandeepmistry/arduino-nRF5)
+
 Program your [Nordic Semiconductor](https://www.nordicsemi.com) nRF51 or nRF52 board using the [Arduino](https://www.arduino.cc) IDE.
 
 Does not require a custom bootloader on the device.