Issue Summary

When parsing email bodies with the header "Content-Type: multipart/mixed; boundary=" the description in the email request is displayed in some meta characters which is not the expected behaviour. 

Example:

The header doesn't have the character set defined.

------=_NextPart_000_0000_01DBE082.BF0E5740
Content-Type: text/plain
Content-Transfer-Encoding: 7bit  

An email that is interpreted properly has the utf-8 charset defined:

--===============7227611776778273978==
MIME-Version: 1.0
Content-Type: text/plain; charset="utf-8" 

Steps to Reproduce

1. Set the email service to use without a charset.
2. Send an email to the email channel.

Expected Results

The description for email requests should match the language of the content in the email body.

Actual Results

The description of the email request is displayed in some meta characters does not correspond to the actual content of the email body....

Workaround

To avoid this issue, user needs to use utf-8 as the charset.