Build cidr-merger from source

dependency.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+set -ex
+
+cidr-merger --version || {
+    curl -sL -o ~/bin/gimme https://raw.githubusercontent.com/travis-ci/gimme/master/gimme
+    chmod +x ~/bin/gimme
+    eval "$(gimme stable)"
+    go get github.com/zhanhb/cidr-merger
+}
+bgptools --version | grep -F $BGPTOOLS_VERSION || \
+    cargo install --vers $BGPTOOLS_VERSION bgptools
+
+cidr-merger --version
+bgptools --version