Unable to create / send new rallypoints to pixhawk using MAVRallyLoader

Hi everyone, I'm trying to send rallypoints to the pixhawk using the methods of the MAVRallyLoader class present in mavwp.py, but when I try to send them to the pixhawk they are not visible on Mission Planner. In what particular way are they to be sent or created?

```
self.rally_loader = mavwp.MAVRallyLoader(self.master.target_system, self.master.target_component)

for rallypoint in list of rallypoints
lat, lon, altitude = something
self.rally_loader.create_and_append_rally_point(int(lat * 1e7), int(lon * 1e7),
int(altitude), int(altitude), 0, 0)

...

for i in range(self.rally_loader.rally_count()):
p = self.rally_loader.rally_point(i)
p.target_system = self.master.target_system
p.target_component = self.master.target_component
p.mission_type = mavutil.mavlink.MAV_MISSION_TYPE_RALLY

self.master.mav.send(p)
```

If instead I create rallypoints using mission planner, then I can override them using the code above, but I can't create new ones anyway. Thanks in advance for the help

Start in mavwp.py with MAVRallyLoader and compare the code path for rallypoints created in Mission Planner with the shown create_and_append_rally_point and master.mav.send calls. Trace what is sent for an existing rallypoint versus a newly created one, and verify the result in Mission Planner. Done means the issue explains or fixes the creation/send path so newly sent rallypoints are visible.

Written by the indexing model from the issue text.