title: bundle exec pod install -> Failed to find known source with the URL "trunk"
body: <p>I'm following some instructions left behind for an Xcode repository.</p>
  <pre><code>$ bundle exec pod install
  Analyzing dependencies
  [!] The version of CocoaPods used to generate the lockfile (1.9.3) is higher than the version of the \
  current executable (1.6.1). Incompatibility issues may arise.
  </code></pre>
  <p>I think this leads to the error:</p>
  <pre><code> Failed to find known source with the URL &quot;trunk&quot;
  </code></pre>
  <p>When I check the version of <code>pods</code>, I get:</p>
  <pre><code>$ pod --version
  1.10.0
  </code></pre>
  <p>My assumption (but I could be wrong), is that I either need to run the command to it runs the newer version of <code>pod</code>, or I need to install the newer version in a different place.</p>
  <p><em><strong>Added info</strong></em>
  (per comment's request)</p>
  <pre><code>$ gem list pod
  
  *** LOCAL GEMS ***
  
  cocoapods (1.10.1, 1.10.0)
  cocoapods-core (1.10.1, 1.10.0)
  cocoapods-deintegrate (1.0.4)
  cocoapods-downloader (1.4.0)
  cocoapods-plugins (1.0.0)
  cocoapods-search (1.0.0)
  cocoapods-trunk (1.5.0)
  cocoapods-try (1.2.0)
  
  
  $ grep -i pod Gemfile.lock
      cocoapods (1.6.1)
        cocoapods-core (= 1.6.1)
        cocoapods-deintegrate (&gt;= 1.0.2, &lt; 2.0)
        cocoapods-downloader (&gt;= 1.2.2, &lt; 2.0)
        cocoapods-plugins (&gt;= 1.0.0, &lt; 2.0)
        cocoapods-search (&gt;= 1.0.0, &lt; 2.0)
        cocoapods-stats (&gt;= 1.0.0, &lt; 2.0)
        cocoapods-trunk (&gt;= 1.3.1, &lt; 2.0)
        cocoapods-try (&gt;= 1.1.0, &lt; 2.0)
      cocoapods-core (1.6.1)
      cocoapods-deintegrate (1.0.4)
      cocoapods-downloader (1.2.2)
      cocoapods-plugins (1.0.0)
      cocoapods-search (1.0.0)
      cocoapods-stats (1.1.0)
      cocoapods-trunk (1.3.1)
      cocoapods-try (1.1.0)
    cocoapods
  </code></pre>