Added attachments handling to ImpersonateMessage
feature #1 Added attachments handling to ImpersonateMessage (Ninir)

This PR was squashed before being merged into the 0.2.x-dev branch (closes #1).

Discussion
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Added attachments handling to ImpersonateMessage

This adds the handling of Attachements to the ImpersonateMessage class, after merging https://github.com/henrikbjorn/Stampie/pull/36.

In order not to break anything, I have to be sure that `"henrikbjorn/stampie": "~0.7",` gets the update, which is not the case at the moment. A tag issue perhaps, as discussed on [Stampie](https://github.com/henrikbjorn/Stampie/pull/36#issuecomment-49405064).

AFAIK, this should wait for the new tag, just to be sure.

Commits
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b12713f Added attachments handling to ImpersonateMessage