Add script/boxen-git-credential

boxen/puppet-git will need to be taught about this file.

script/boxen-git-credential

@@ -0,0 +1,33 @@
+#!/usr/bin/ruby
+# Provide git credentials using Boxen's config.
+
+unless command = ARGV.shift
+  this = File.basename $0
+  abort "Usage: #{this} <get|store|erase>"
+end
+
+# We only support get.
+
+exit 0 unless command == "get"
+
+# Make sure we're looking for github.com stuff.
+
+attrs = Hash[$stdin.read.split($/).map { |l| l.split("=") }]
+exit 1 unless attrs["host"] == "github.com"
+
+require "pathname"
+
+# Put us where we belong, in the root dir of our boxen repo.
+
+Dir.chdir Pathname.new(__FILE__).realpath + "../.."
+
+# Set up our local configuration, deps, and load path.
+
+load "config/basic.rb"
+
+require "boxen/config"
+
+config = Boxen::Config.load
+
+puts "username=#{config.login}"
+puts "password=#{config.password}"