title: Can't install RMagick 0.0.0. Can't find Magick-config
body: <p>I'm running a debian server and upgraded all packages after quite a while (<code>apt-get update</code>, <code>apt-get upgrade</code>, <code>apt-get distro-upgrade</code>). Then rmagick didn't work anymore becuase imagemagick was updated.</p>
  
  <p>So I ran:</p>
  
  <pre><code>gem uninstall rmagick
  bundle install
  </code></pre>
  
  <p>Then I got this:</p>
  
  <pre><code>Gem::Ext::BuildError: ERROR: Failed to build gem native extension.
  
      /usr/local/bin/ruby extconf.rb
  checking for Ruby version &gt;= 1.8.5... yes
  checking for gcc... yes
  checking for Magick-config... no
  Can't install RMagick 0.0.0. Can't find Magick-config in /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
  
  *** extconf.rb failed ***
  Could not create Makefile due to some reason, probably lack of necessary
  libraries and/or headers.  Check the mkmf.log file for more details.  You may
  need configuration options.
  
  Provided configuration options:
      --with-opt-dir
      --without-opt-dir
      --with-opt-include
      --without-opt-include=${opt-dir}/include
      --with-opt-lib
      --without-opt-lib=${opt-dir}/lib
      --with-make-prog
      --without-make-prog
      --srcdir=.
      --curdir
      --ruby=/usr/local/bin/ruby
  
  extconf failed, exit code 1
  
  Gem files will remain installed in /srv/www/www.example.com/shared/vendor/bundle/ruby/2.1.0/gems/rmagick-2.13.3 for inspection.
  Results logged to /srv/www/www.example.com/shared/vendor/bundle/ruby/2.1.0/extensions/x86_64-linux/2.1.0-static/rmagick-2.13.3/gem_make.out
  An error occurred while installing rmagick (2.13.3), and Bundler cannot continue.
  Make sure that `gem install rmagick -v '2.13.3'` succeeds before bundling.
  </code></pre>
  
  <p>This is <code>cat mkmf.log</code>:</p>
  
  <pre><code>    checking for Ruby version &gt;= 1.8.5... -------------------- yes
  
  --------------------
  
  find_executable: checking for gcc... -------------------- yes
  
  --------------------
  
  find_executable: checking for Magick-config... -------------------- no
  
  --------------------
  
  Can't install RMagick 0.0.0. Can't find Magick-config in /usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
  </code></pre>
  
  <p>Can anyone help me with this?</p>