Install libsqlite3 using homebrew on OSX

.travis.yml

@@ -1,9 +1,15 @@
+sudo: required
+dist: trusty
+os:
+  - linux
+  - osx
 language: go
 go:
   - 1.5
   - 1.6
   - tip
 before_install:
+  - ./.travis/install.sh
   - go get github.com/mattn/goveralls
   - go get golang.org/x/tools/cmd/cover
 script:

.travis/install.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+if [[ $TRAVIS_OS_NAME == "osx" ]]; then
+    brew install libsqlite3
+fi