Add pinned_links cache clear

Author: ArtOfCode-

scripts/clear_cache.rb

@@ -1 +1,4 @@
-Rails.cache.delete_matched 'network/*'
+Rails.cache.delete_matched 'network/*'
+RequestContext.redis.keys('*pinned_links').each do |key|
+  RequestContext.redis.del(key)
+end