2524 it should be possible to attach a file to an e mail

[lbownik]

Currently when a user writes a message using contact form, s/he cannot attach any files.
We should allow it, as in some cases attaching additional information (a file causing problems, a screenshot).
We may add "Attach files" button under the "Message" textbox.

Expectations:

• It should be possible to add multiple files, but no more than 5.
• Total size of files should not exceed 10MB (the e-mail it should exceed quota of standard ICM mailbox).
• Files added by the user should be attached to the eventual e-mail message.