Extend metadata sent to Equella during selection/contribution

[abidingotter]

Currently we send some limited metadata to Equella when doing a drag and drop contribution, but this should be extended to include the course category and section of the file being dropped into as well as information about the user.

This metadata should also be sent to Equella during a normal selection session, so any new contributions during the session will take on the metadata.

The format of the XML sent to Equella will be:

<integration>
    <lms>Moodle</lms>
    <contributiontype>integration</contributiontype>
    <moodle>
        <course>
            <idnumber>eq101</idnumber>
            <id>2</id>
        </course>
        <section>Topic 1</section>
        <category>
            <name>BMS1011 S1 2017</name>
            <category>
                <name>S1</name>
                <category>
                    <name>2017</name>
                </category>
            </category>
        </category>
    </moodle>
    <user>
        <username>admin</username>
        <firstname>Admin</firstname>
        <lastname>User</lastname>
    </user>
    <course>
        <fullname>Equella 101</fullname>
        <shortname>eq101</shortname>
        <code>eq101</code>
    </course>
</integration>

Contribution type will either be "quick" as per existing drag and drop integration, or "integration" for the standard integration experience.

The "moodle" section is for Moodle specific data, the rest of the information is LMS agnostic and could be sent from other LMS modules (E.g. Blackboard Building Block)

[mrblippy]

Verified in 2018.2 and 6.6