GRN2-225, GRN2-227: Images sent by Office365 Institutional accounts break the rooms (#753)

* Validate profile image url

* Add rake task to migrate old office365 accounts

app/helpers/application_helper.rb

@@ -17,6 +17,7 @@
 # with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
 
 require 'bbb_api'
+require 'uri'
 require 'i18n/language/mapping'
 
 module ApplicationHelper
@@ -139,4 +140,11 @@ module ApplicationHelper
   def google_analytics_url
     "https://www.googletagmanager.com/gtag/js?id=#{ENV['GOOGLE_ANALYTICS_TRACKING_ID']}"
   end
+
+  def valid_url?(input)
+    uri = URI.parse(input)
+    !uri.host.nil?
+  rescue URI::InvalidURIError
+    false
+  end
 end