Improve pkg_appdata readability

Moving .first to the pkg_appdata assignment makes checking if a first
element exists easier, a simple if pkg_appdata can be used. Assignments
for @name, @appcategories and @homepage are also slightly nicer to read.

app/controllers/package_controller.rb

@@ -20,11 +20,11 @@ def show
       @default_package = @packages.select { |s| s.project == "#{@baseproject}:Update" }.first ||
                          @packages.select { |s| [@baseproject, "#{@baseproject}:NonFree"].include? s.project }.first
 
-      pkg_appdata = @appdata[:apps].select { |app| app[:pkgname].downcase == @pkgname.downcase }
-      if !pkg_appdata.first.blank?
-        @name = pkg_appdata.first[:name]
-        @appcategories = pkg_appdata.first[:categories]
-        @homepage = pkg_appdata.first[:homepage]
+      pkg_appdata = @appdata[:apps].select { |app| app[:pkgname].downcase == @pkgname.downcase }.first
+      if pkg_appdata
+        @name = pkg_appdata[:name]
+        @appcategories = pkg_appdata[:categories]
+        @homepage = pkg_appdata[:homepage]
       end
 
       @screenshot = url_for :controller => :package, :action => :screenshot, :package => @pkgname, protocol: request.protocol