nvchecker.ini: let the following ruby packages track gems

ruby-{kramdown,colorator,liquid-3,mercenary,rouge,safe_yaml,maruku,rb-fsevent,rb-inotify,yard,sass,ffi,jekyll-sass-converter,listen,forwardable-extended,pathutil,jekyll-watch,jekyll}

nvchecker.ini

@@ -1655,58 +1655,58 @@ aur =
 github = lastavenger/srain
 
 [ruby-kramdown]
-aur=
+gems = kramdown
 
 [ruby-colorator]
-aur=
+gems = colorator
 
 [ruby-liquid-3]
-aur=
+gems = liquid
 
 [ruby-mercenary]
-aur=
+gems = mercenary
 
 [ruby-rouge]
-aur=
+gems = rouge
 
 [ruby-safe_yaml]
-aur=
+gems = safe_yaml
 
 [ruby-maruku]
-aur=
+gems = maruku
 
 [ruby-rb-fsevent]
-aur=
+gems = rb-fsevent
 
 [ruby-rb-inotify]
-aur=
+gems = rb-inotify
 
 [ruby-yard]
-aur=
+gems = yard
 
 [ruby-sass]
-aur=
+gems = sass
 
 [ruby-ffi]
-aur=
+gems = ffi
 
 [ruby-jekyll-sass-converter]
-aur=
+gems = jekyll-sass-converter
 
 [ruby-listen]
-aur=
+gems = listen
 
 [ruby-forwardable-extended]
-aur=
+gems = forwardable-extended
 
 [ruby-pathutil]
-aur=
+gems = pathutil
 
 [ruby-jekyll-watch]
-aur=
+gems = jekyll-watch
 
 [ruby-jekyll]
-aur=
+gems = jekyll
 
 [nodejs-gitbook]
 aur=