title: Change master page for all sites
body: <p>I have a new master which has to be applied on all of my sites.
  But I don't know to change the content of my odler master page in database (for all sites) via Powershell. I know how iterate my sites and modify the url of the master page, but me I just want to change the CONTENT of my master page.</p>
  
  <p>Thanks for your help</p>