Priority mapping is incorrect

[zotanmew]

The sync docs API read:

priority: Integer
The priority of the task (a number between 1 and 4, 4 for very urgent and 1 for natural).
Note: Keep in mind that very urgent is the priority 1 on clients. So, p1 will return 4 in the API.

This is not currently reflected in the Priority model. Either the enum member names, or both the names and the values should be adjusted to reflect the actual priority.

[zotanmew]

I'm happy to PR this if you could tell me which variant you'd prefer.

[olsh]

Either the enum member names, or both the names and the values should be adjusted to reflect the actual priority.

This is a breaking change anyway, so let's update both.

[zotanmew]

Alright, I'll implement it after touching up the previous PR.