Remove mentors from the EDP

The mentoring concept doesn't generally work as we had intended/hoped.

• It's difficult to identify a mentor: very often project creation is delayed because we can't get anybody to volunteer;
• Mentorship is basically passive: In general, mentors do not actively engage in projects resulting in the relationship having dubious value;
• The EMO is much more effective at helping get projects up to speed; and
• Other resources exist now that did not exist when the notion of mentoring was introduced (e.g., the incubation mailing list).

Let's remove the notion of mentors from the EDP. We'll target delivery to the EF Board of Directors for their approval by the end of 2023Q2.