fix #2091 new analytics

fix #2091 new analytics

# Done

* WPAnalyticsStatLoginFailed - LOGIN_FAILED, it's not implemented in iOS, so I chose the String "Login - Failed Login" as event name. (Should we add a property to track why the user can't login? 2fa, invalid username/pwd, invalid url, other)
* WPAnalyticsStatLoginFailedToGuessXMLRPC - LOGIN_FAILED_TO_GUESS_XMLRPC, it's not implemented in iOS, so I chose the String "Login - Failed To Guess XMLRPC" as event name.
* WPAnalyticsStatEditorTappedBlockquote - EDITOR_TAPPED_BLOCKQUOTE,
* WPAnalyticsStatEditorTappedBold - EDITOR_TAPPED_BOLD,
* WPAnalyticsStatEditorTappedImage - EDITOR_TAPPED_IMAGE,
* WPAnalyticsStatEditorTappedItalic - EDITOR_TAPPED_ITALIC, called "Editor - Tapped Italics Button" (Italics with an "s"), like here https://github.com/wordpress-mobile/WordPress-iOS/blob/4dee05377d103e1d33df4a47ccc5f8f7542876d0/WordPress/Classes/Utility/Analytics/WPAnalyticsTrackerMixpanel.m#L336
* WPAnalyticsStatEditorTappedLink - EDITOR_TAPPED_LINK,
* WPAnalyticsStatEditorTappedMore - EDITOR_TAPPED_MORE,
* WPAnalyticsStatEditorTappedStrikethrough - EDITOR_TAPPED_STRIKETHROUGH,
* WPAnalyticsStatEditorTappedUnderline - EDITOR_TAPPED_UNDERLINE,
* WPAnalyticsStatSupportOpenedHelpshiftScreen - SUPPORT_OPENED_HELPSHIFT_SCREEN, open Helpshift Support or FAQ (we can create 2 different events) - also it's not implemented in iOS, so I chose the String "Support - Opened Helpshift Screen" as event name.
* WPAnalyticsStatNotificationLiked - NOTIFICATION_LIKED
* WPAnalyticsStatNotificationUnliked - NOTIFICATION_UNLIKED
* WPAnalyticsStatNotificationApproved - NOTIFICATION_UNAPPROVED
* WPAnalyticsStatNotificationUnapproved - NOTIFICATION_UNAPPROVED


# Doesn't exists (yet) in wpandroid or can't be implemented

* WPAnalyticsStatEditorDiscardedChanges, users can't discard changes (posts are auto saved)
* WPAnalyticsStatEditorTappedHTML, no way to switch to html in the editor
* WPAnalyticsStatEditorTappedOrderedList, no list button
* WPAnalyticsStatEditorTappedUnorderedList, no list button
* WPAnalyticsStatEditorTappedUnlink, no unlink button
* WPAnalyticsStatSupportSentMessage, can't be detected (Helpshift is a closed source black box, once we open their Activity we can't track anything)
* WPAnalyticsStatSupportSentReplyToSupportMessage, can't be detected (Helpshift is a closed source black box, once we open their Activity we can't track anything)
* WPAnalyticsStatSupportReceivedResponseFromSupport, can only be detected from push notifications (not if the user "chat" with a HE) - so we're going to miss most of the responses
* WPAnalyticsStatSelectedLearnMoreInConnectToJetpackScreen,There is no "Learn More" button in the connect to Jetpack screen (only "Install Jetpack" or "Cancel").
* WPAnalyticsStatAddedSelfHostedSiteButJetpackNotConnectedToWPCom, we don't request Jetpack connection when a user adds a self hosted blog
* WPAnalyticsStatSkippedConnectingToJetpack, we don't request Jetpack connection when a user adds a self hosted blog (we only ask this when he tries to connect to the Stats, and it's the default WPcom login dialog, not differentiated from a wpcom login issue).
* WPAnalyticsStatNotificationsMissingSyncWarning, I can't find corresponding code in wpandroid
* WPAnalyticsStatNotificationFollowAction, we don't have follow links in notification anymore
* WPAnalyticsStatNotificationUnfollowAction, we don't have follow links in notification anymore