Dependency for libvips in debian

[musover]

When attempting to deploy the latest commit (9957c4c), I ran into some issues referencing libvips, which were not resolved until I installed libvips42, libvips-dev and libvips-tools on the debian system I was running danbooru out of. These are the logs that led me to such a conclusion.

danbooru@danbooru:~/danbooru$ bundle exec rails server
Traceback (most recent call last):
        39: from bin/rails:4:in `<main>'
        38: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:292:in `require'
        37: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:258:in `load_dependency'
        36: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:292:in `block in require'
        35: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:17:in `require'
        34: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:17:in `require'
        33: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.1.6/lib/rails/commands.rb:16:in `<main>'
        32: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.1.6/lib/rails/command.rb:44:in `invoke'
        31: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.1.6/lib/rails/command/base.rb:63:in `perform'
        30: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor.rb:387:in `dispatch'
        29: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/invocation.rb:126:in `invoke_command'
        28: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/thor-0.20.0/lib/thor/command.rb:27:in `run'
        27: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.1.6/lib/rails/commands/server/server_command.rb:130:in `perform'
        26: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.1.6/lib/rails/commands/server/server_command.rb:130:in `tap'
        25: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/railties-5.1.6/lib/rails/commands/server/server_command.rb:133:in `block in perform'
        24: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:292:in `require'
        23: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:258:in `load_dependency'
        22: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:292:in `block in require'
        21: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:17:in `require'
        20: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:17:in `require'
        19: from /home/danbooru/danbooru/config/application.rb:5:in `<main>'
        18: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler.rb:114:in `require'
        17: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/runtime.rb:65:in `require'
        16: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/runtime.rb:65:in `each'
        15: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/runtime.rb:76:in `block in require'
        14: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/runtime.rb:76:in `each'
        13: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/runtime.rb:81:in `block (2 levels) in require'
        12: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:50:in `require'
        11: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:50:in `require'
        10: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/ruby-vips-2.0.9/lib/ruby-vips.rb:1:in `<main>'
         9: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:292:in `require'
         8: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:258:in `load_dependency'
         7: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/activesupport-5.1.6/lib/active_support/dependencies.rb:292:in `block in require'
         6: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:17:in `require'
         5: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bootsnap-1.1.8/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:17:in `require'
         4: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/ruby-vips-2.0.9/lib/vips.rb:457:in `<main>'
         3: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/ruby-vips-2.0.9/lib/vips.rb:466:in `<module:Vips>'
         2: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/ffi-1.9.18/lib/ffi/library.rb:100:in `ffi_lib'
         1: from /home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/ffi-1.9.18/lib/ffi/library.rb:100:in `map'
/home/danbooru/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/ffi-1.9.18/lib/ffi/library.rb:147:in `block in ffi_lib': Could not open library 'vips': vips: cannot open shared object file: No such file or directory. (LoadError)
Could not open library 'libvips.so': libvips.so: cannot open shared object file: No such file or directory

To resolve this, perhaps in the INSTALL.debian script, in line 38 libvips42, libvips-tools and libvips-dev should be appended.