IMAP accounts required when not used

[minsis]

IMAP accounts are a required in config but we don't use IMAP. Simply using this module to send notifications via smtp.

[amanda11]

imap_accounts can be set to [] to indicate that there are no imap accounts to use in that case.

[minsis]

While this does work, requiring entry should be optional for both imap and smtp and allowing the user to select the options they need.

[AzyCrw4282]

Encountered the same issue today with only requiring smtp. I second your solution.

[MaheshSankaran]

Am also encountered same issue