Ensure the email doesn't already exist before creating it.

Reviewed-By: Jared Hancock <jared@osticket.com>

html: Drop xml processing instructions from email

Reviewed-By: Peter Rotich <peter@osticket.com>

mysqli: Numbers with leading zeros are strings

Reviewed-By: Peter Rotich <peter@osticket.com>

Fix ambiguous `due date` if specified as custom field

Reviewed-By: Peter Rotich <peter@osticket.com>

Allow manager to be set even when a department has no members

Reviewed-By: Jared Hancock <jared@osticket.com>

This is necessary to allow for creative department based access control and
alerts.

Fix canned append in non-HTML mode

Reviewed-By: Peter Rotich <peter@osticket.com>

Preserve inline image floating in ticket thread

Reviewed-By: Peter Rotich <peter@osticket.com>

Careful transcoding attachments with a charset

Reviewed-By: Peter Rotich <peter@osticket.com>

tnef: Strip null bytes from attachment filenames

Reviewed-By: Peter Rotich <peter@osticket.com>

If a non-text attachment specifies a charset in the content-type header,
don't transcode the content before saving it to the database. This can
corrupt attachments which have a header like the following:

Content-Type: application/pdf; charset=UTF-8

Since a PDF contains binary data, coercing it to UTF-8 encoding will drop
characters not valid in UTF-8 and will corrupt the attachment data.

Also support the TransportName in the properties list and prefer it over the
attachment-level attribute, as it is Unicode encoded.

filter: Implement priority 

Reviewed-By: Peter Rotich <peter@osticket.com>

The priority setting was broken when priority was added to the dynamic data

Register session close on shutdown at the start of session handling

Reviewed-By: Jared Hancock <jared@osticket.com>

pipe: Honor attachment ext and size restrictions

Reviewed-By: Peter Rotich <peter@osticket.com>

smtp: Reuse existing connections where possible

Reviewed-By: Peter Rotich <peter@osticket.com>

tnef: Support TNEF for fetched emails

Reviewed-By: Peter Rotich <peter@osticket.com>

This is necessary to make sure session data is saved on redirect.

Previously, the data blocks were inspected byte for byte. Now data blocks
are parsed 1k at a time. Fewer PHP function calls ultimately means faster
performance.

Parse Microsoft TNEF email attachments

Peter Rotich <peter@osticket.com>

Shift error checking into Mail_Parse::parseAddressList

Reviewed-By: Jared Hancock <jared@osticket.com>

This should speed up the system where several emails and alerts will be sent
through the same SMTP account in the same request.

Simplify workflow for new ticket by staff

Reviewed-By: Peter Rotich <peter@osticket.com>