add events around upgrade process

services/web/public/coffee/history/HistoryManager.coffee

@@ -42,8 +42,10 @@ define [
 				@view.setHistoryAreaToDisplayEnableVersioning()
 
 		enableVersioning: ->
+			ga('send', 'event', 'subscription-funnel', 'askToUpgrade', {history:true})
 			AccountManager.askToUpgrade @ide,
 				onUpgrade: () =>
+					ga('send', 'event', 'subscription-funnel', 'upgraded-free-trial', {history:true})
 					@showHistoryArea()
 
 		takeSnapshot: (message, callback = (error) ->) ->

services/web/public/coffee/project-members/ProjectMembersManager.coffee

@@ -81,9 +81,12 @@ define [
 					@ide.showGenericServerErrorMessage()
 					return
 				if !added
+					ga('send', 'event', 'subscription-funnel', 'askToUpgrade', {projectMemebrs:true})
 					AccountManager.askToUpgrade @ide,
 						why: "to add additional collaborators"
-						onUpgrade: () => @addMember(email, privileges)
+						onUpgrade: () => 
+							ga('send', 'event', 'subscription-funnel', 'upgraded-free-trial', {projectMemebrs:true})
+							@addMember(email, privileges)
 
 		afterMemberRemoved: (memberId) ->
 			for member in @members.models

services/web/public/coffee/settings/DropboxSettingsManager.coffee

@@ -17,8 +17,11 @@ define [
 					@tab.empty()
 					if !@ide.isAllowedToDoIt "owner"
 					else if !@project.get('features').dropbox
+						ga('send', 'event', 'subscription-funnel', 'askToUpgrade', {dropbox:true})
 						accountManager.askToUpgrade @ide,
-							onUpgrade: @checkIfUserIsLinkedToDropbox
+							onUpgrade: =>
+								@checkIfUserIsLinkedToDropbox()
+								ga('send', 'event', 'subscription-funnel', 'upgraded-free-trial', {dropbox:true})
 					else
 						@checkIfUserIsLinkedToDropbox()