Transition to MastoAPI: Mute & Block and Add Mutes management tab

As the second part of #227 (closed), this will show back Mutes tab under user settings page along with proper API integration.

• Show back Mutes tab
• Switch all endpoints related to mute and block to MastoAPI
• Reset mutes and blocks while fetching new mutes and blocks
• Add Hide posts of muted users option to the settings page; if it is enabled, it won't fetch statuses of muted users at all with help of pleroma!872 (merged)

Screenshots:

UI:

src/components/mute_card/mute_card.js

@@ -12,7 +12,7 @@ const MuteCard = {
       return this.$store.getters.findUser(this.userId)
     },
     muted () {
-      return this.user.mastodonMuted
+      return this.user.muted
     }
   },
   components: {