Use Yarn to manage dependencies, cleanup unused bootstrap libs (#6436)

lib/tasks/javascript.rake

@@ -0,0 +1,100 @@
+def public_js
+  "#{Rails.root}/public/javascripts"
+end
+
+def vendor_js
+  "#{Rails.root}/vendor/assets/javascripts"
+end
+
+def library_src
+  "#{Rails.root}/node_modules"
+end
+
+task 'javascript:update' do
+
+  require 'uglifier'
+
+  yarn = system("yarn install")
+  abort('Unable to run "yarn install"') unless yarn
+
+  dependencies = [
+    {
+      source: 'ace-builds/src-min',
+      destination: 'ace',
+      public: true
+    }, {
+      source: 'chart.js/dist/Chart.min.js',
+      public: true
+    }, {
+      source: 'magnific-popup/dist/jquery.magnific-popup.min.js',
+      public: true
+    }, {
+      source: 'pikaday/pikaday.js',
+      public: true
+    }, {
+      source: 'spectrum-colorpicker/spectrum.js',
+      uglify: true,
+      public: true
+    }, {
+      source: 'spectrum-colorpicker/spectrum.css',
+      public: true
+    }, {
+      source: 'favcount/favcount.js'
+    }, {
+      source: 'handlebars/dist/handlebars.js'
+    }, {
+      source: 'handlebars/dist/handlebars.runtime.js'
+    }, {
+      source: 'htmlparser/lib/htmlparser.js'
+    }, {
+      source: 'jquery-resize/jquery.ba-resize.js'
+    }, {
+      source: 'jquery.autoellipsis/src/jquery.autoellipsis.js',
+      destination: 'jquery.autoellipsis-1.0.10.js'
+    }, {
+      source: 'jquery-color/jquery.color.js'
+    }, {
+      source: 'jquery.cookie/jquery.cookie.js'
+    }, {
+      source: 'jQuery/dist/jquery.js'
+    }, {
+      source: 'jquery-tags-input/src/jquery.tagsinput.js'
+    }, {
+      source: 'markdown-it/dist/markdown-it.js'
+    }, {
+      source: 'mousetrap/mousetrap.js'
+    }, {
+      source: 'resumablejs/resumable.js'
+    }
+  ]
+
+  start = Time.now
+
+  dependencies.each do |f|
+    src = "#{library_src}/#{f[:source]}"
+
+    unless f[:destination]
+      filename = f[:source].split("/").last
+    else
+      filename = f[:destination]
+    end
+
+    if f[:public]
+      dest = "#{public_js}/#{filename}"
+    else
+      dest = "#{vendor_js}/#{filename}"
+    end
+
+    unless File.exists?(dest)
+      STDERR.puts "New dependency added: #{dest}"
+    end
+
+    if f[:uglify]
+      File.write(dest, Uglifier.new.compile(File.read(src)))
+    else
+      FileUtils.cp_r(src, dest)
+    end
+  end
+
+  STDERR.puts "Completed copying dependencies: #{(Time.now - start).round(2)} secs"
+end