PLT-5308 Caching layer part 2 (#6973)

* Adding Reaction store cache layer example

* Implementing reaction store in new caching system.

* Redis for reaction store

* Adding redis library

* Adding invalidation for DeleteAllWithEmojiName and other minor enhancements

vendor/github.com/go-redis/redis/testdata/redis.conf

@@ -0,0 +1,10 @@
+# Minimal redis.conf
+
+port 6379
+daemonize no
+dir .
+save ""
+appendonly yes
+cluster-config-file nodes.conf
+cluster-node-timeout 30000
+maxclients 1001