title: gem rMagick is not installing on ubuntu 18.04
body: <p>I am working on rails 4.2.7 app. The app was working fine few days ago but suddenly When i try to install bundle it gives error....' </p>
  
  <pre><code>An error occurred while installing rmagick (2.15.4), and Bundler 
  cannot continue.
  Make sure that `gem install rmagick -v '2.15.4' --source 
  'https://rubygems.org/'` succeeds before bundling.'
  </code></pre>
  
  <p>When i run "gem install rmagick -v '2.15.4" it gives error</p>
  
  <pre><code>Building native extensions. This could take a while...
  ERROR:  Error installing rmagick:
  ERROR: Failed to build gem native extension.
  
  current directory: /home/shahroz/.rvm/gems/ruby-2.2.3@hh-web- 
  platform/gems/rmagick-2.15.4/ext/RMagick
  /home/shahroz/.rvm/rubies/ruby-2.2.3/bin/ruby -r ./siteconf20190411- 
  829-1e8ve9u.rb extconf.rb
  checking for gcc... yes
  checking for Magick-config... no
  checking for pkg-config... yes
  checking for outdated ImageMagick version (&lt;= 6.4.9)... no
  checking for Ruby version &gt;= 1.8.5... yes
  checking for stdint.h... yes
  checking for sys/types.h... yes
  checking for wand/MagickWand.h... no
  
  Can't install RMagick 2.15.4. Can't find MagickWand.h.
  *** 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=/home/shahroz/.rvm/rubies/ruby- 
     2.2.3/bin/$(RUBY_BASE_NAME)
  
     To see why this extension failed to compile, please check the 
     mkmf.log which can be found here:
  
      /home/shahroz/.rvm/gems/ruby-2.2.3@hh-web- 
     platform/extensions/x86_64- 
     linux/2.2.0/rmagick-2.15.4/mkmf.log
  
     extconf failed, exit code 1
  
     Gem files will remain installed in /home/shahroz/.rvm/gems/ruby- 
     2.2.3@hh-web-platform/gems/rmagick-2.15.4 for inspection.
     Results logged to /home/shahroz/.rvm/gems/ruby-2.2.3@hh-web- 
    platform/extensions/x86_64-linux/2.2.0/rmagick-2.15.4/gem_make.out
  </code></pre>
  
  <p>I tried the following commands but nothing worked for me,</p>
  
  <pre><code>sudo apt-get install graphicsmagick-libmagick-dev-compat 
  libmagickcore-dev libmagickwand-dev
  
  sudo apt-get install libmagickwand-dev imagemagick
  </code></pre>
  
  <p>i want gem rmagick to be installed.</p>