Migrate to dep for dependency management (#26)

* Replace `Godeps` with `dep`
* Upgrade all dependencies
* Remove vendor source from git repository

Gopkg.lock

@@ -0,0 +1,63 @@
+# This file is autogenerated, do not edit; changes may be undone by the next 'dep ensure'.
+
+
+[[projects]]
+  name = "github.com/davecgh/go-spew"
+  packages = ["spew"]
+  revision = "346938d642f2ec3594ed81d874461961cd0faa76"
+  version = "v1.1.0"
+
+[[projects]]
+  branch = "master"
+  name = "github.com/go-sql-driver/mysql"
+  packages = ["."]
+  revision = "2cc627ac8defc45d65066ae98f898166f580f9a4"
+
+[[projects]]
+  name = "github.com/joho/godotenv"
+  packages = ["."]
+  revision = "a79fa1e548e2c689c241d10173efd51e5d689d5b"
+  version = "v1.2.0"
+
+[[projects]]
+  branch = "master"
+  name = "github.com/lib/pq"
+  packages = [".","oid"]
+  revision = "19c8e9ad00952ce0c64489b60e8df88bb16dd514"
+
+[[projects]]
+  name = "github.com/mattn/go-sqlite3"
+  packages = ["."]
+  revision = "6c771bb9887719704b210e87e934f08be014bdb1"
+  version = "v1.6.0"
+
+[[projects]]
+  name = "github.com/pmezard/go-difflib"
+  packages = ["difflib"]
+  revision = "792786c7400a136282c1664665ae0a8db921c6c2"
+  version = "v1.0.0"
+
+[[projects]]
+  name = "github.com/stretchr/testify"
+  packages = ["assert","require"]
+  revision = "b91bfb9ebec76498946beb6af7c0230c7cc7ba6c"
+  version = "v1.2.0"
+
+[[projects]]
+  name = "github.com/urfave/cli"
+  packages = ["."]
+  revision = "cfb38830724cc34fedffe9a2a29fb54fa9169cd1"
+  version = "v1.20.0"
+
+[[projects]]
+  name = "google.golang.org/appengine"
+  packages = ["cloudsql"]
+  revision = "150dc57a1b433e64154302bdc40b6bb8aefa313a"
+  version = "v1.0.0"
+
+[solve-meta]
+  analyzer-name = "dep"
+  analyzer-version = 1
+  inputs-digest = "529ecf990d8fb0e342075bd8e761e40430b28293be2e4fd889d06d12ef978957"
+  solver-name = "gps-cdcl"
+  solver-version = 1