title: Add-Migration : Exception calling "AddFromFile" with "1" argument(s): "'basePath' cannot be an empty string ("")
body: <p>I get an error when I to run add-migration with entitcore on any dotnetcore based project but the equivalent command works when targeting the full dotnetframework</p>
  
  <p>Add-Migration : Exception calling "AddFromFile" with "1" argument(s): "'basePath' cannot be an empty string ("") </p>
  
  <p>see a snapshot of my code. It's a dotnetcore console app. Thesame will work if created the project based on dotnetframewok 4.6.1
  <a href="https://i.stack.imgur.com/mxYGU.png" rel="noreferrer"><img src="https://i.stack.imgur.com/mxYGU.png" alt="enter image description here"></a> </p>