drag and drop files into sidebar

[msphair]

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[msphair]

starting on this will likely entail handling an event similar to our "changed", "create", "rename", "delete" event handlers in oblogger_view.ts.

• get a console log when you drop something in
  • use the console log to print out details about what we receive from the drop event
• figure out correct functionality depending on conditions
  • what if the file already exists?
  • if the file is dropped on a tag group, does it try to add that tag to the file so it shows up there?
  • do we even want to handle "where" it was dropped and instead just handle "it was dropped on oblogger" and bring it into wherever the user has set to create new notes?