Bugfix for Sitecore 9 SocialConnect module creating items with an invalid name

MessageList.ascx.cs

...
protected void SavePostMessage(string network, string NewtworkPagename, string postid, string pageid, ....)
{
      try
      {
           using (SecurityDisabler securityDisabler = new SecurityDisabler())
           {
               Database database = Factory.GetDatabase("master");
               Item item = database.GetItem("/sitecore/system/Social/PostMessage");
               TemplateItem template = database.GetTemplate(SocialTemplates.SocialMessages.ID);
               DateTime utcNow = DateTime.UtcNow;
               string itemname = string.Concat(network, utcNow.ToString().Replace("/", "").Replace("\\", "").Replace(" ", "-").Replace(":", ""), "-", pagename);
               itemname = itemname.Replace("\\", "").Replace("/", "").Replace(":", "").Replace("<", "").Replace(">", "").Replace("[", "").Replace("]", "");
               itemname = Sitecore.Data.Items.ItemUtil.ProposeValidItemName(itemname); // new line of code, create a valid item name for the Sitecore-item.                                                                
               ...

protected void SavePostMessageWithShedule(string network, string NewtworkPagename, string postid, string pageid, ....)
{
               ...
               itemname = Sitecore.Data.Items.ItemUtil.ProposeValidItemName(itemname); // new line of code, create a valid item name for the Sitecore-item.                                                                
               ...