title: `bundle install` fails (because of git protocol)
body: <p>With this simple Gemfile, </p>
  
  <pre><code>source 'https://rubygems.org'
  gem 'activerecord', "~&gt; 2.2.3"
  gem 'activerecord-sqlserver-adapter', github: 'arthrex/activerecord-sqlserver-adapter', :branch =&gt; '2-3-stable'
  </code></pre>
  
  <p><code>bundle install</code> fails with </p>
  
  <pre><code>Fetching git://github.com/arthrex/activerecord-sqlserver-adapter.git
  fatal: unable to connect to github.com:
  github.com[0: 192.30.252.131]: errno=No error
  
  Git error: command `git clone
  "git://github.com/arthrex/activerecord-sqlserver-adapter.git"
  "c:/Languages/Ruby/1.9.3/lib/ruby/gems/1.9.1/cache/bundler/git/activerecord-sqlserver-adapter-8019982c6a12a1297e8a135275
  d94bdee6cd893b"
  --bare --no-hardlinks` in directory c:/Users/BZISAD0/Code/CSV has failed.
  </code></pre>
  
  <p>At first I thought my proxy configurations were screwed up but I can execute this command with no problem:</p>
  
  <pre><code>$ git clone http://github.com/arthrex/activerecord-sqlserver-adapter.git
  </code></pre>
  
  <p>With the git protocol, however, it fails:</p>
  
  <pre><code>$ git clone git://github.com/arthrex/activerecord-sqlserver-adapter.git
  Cloning into 'activerecord-sqlserver-adapter'...
  fatal: unable to connect to github.com:
  github.com[0: 192.30.252.130]: errno=No error
  </code></pre>
  
  <p>so I'm inferring that the proxy is not playing nice with the git protocol.  At any rate, for whatever reason, http is working fine but the git protocol is not.</p>
  
  <p>Is there a way to work around this?  E.g. configuring the use of <code>http://</code> rather than <code>git://</code> in my <code>~/.gitconfig</code>?</p>