public async Task<IHttpActionResult> PostParticipant(Participant participant)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }
            participant.ParticipantID = Guid.NewGuid();
            Guid valid_id = Guid.NewGuid();
            participant.ValidationID = valid_id;
            participant.Activated = false;
            participant.DateCreated = DateTime.Today;

            db.Participants.Add(participant);

            try
            {
                await db.SaveChangesAsync();
            }
            catch (DbUpdateException)
            {
                if (ParticipantExists(participant.ParticipantID))
                {
                    return Conflict();
                }
                else
                {
                    throw;
                }
            }

            return CreatedAtRoute("DefaultApi", new { id = participant.ParticipantID }, participant);
        }
        public async Task<IHttpActionResult> PutParticipant(Guid id, Participant participant)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            if (id != participant.ParticipantID)
            {
                return BadRequest();
            }

            db.Entry(participant).State = EntityState.Modified;

            try
            {
                await db.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!ParticipantExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return StatusCode(HttpStatusCode.NoContent);
        }