[15] Problem with e-mail sender refresh after user removal

[JaRutkowski]

[JaRutkowski]

The problem&solution short description:
After adding/removing the Client appropriate components in the 'e-mail module' weren't refreshed. F.eg. outbox/draft table, recipients combo boxes. The problem was solved by invoking 'reloading' methods, which are added to the Params. Additionally, before the Client deletion execution, the session's clear method is invoked.

@MatSzymczyk, please be informed.