This allows both tspend and treasury policies to be set by clients on a per-ticket basis. Preferences can be set when initially registering a ticket with `/payfee`, and can be later updated using `/setvotechoices`.
Any requests which alter treasury/tspend policy will be stored in the database using the existing accountability system.
**Note:** This does not include consistency checking, it will need to be added later when dcrwallet has an RPC to retrieve policies in batches.
* Add network proportion to homepage and /vspinfo.
Proportion is calculated using the number of tickets currently registered with the VSP, divided by the total size of the network ticket pool as reported by `getblockheader`.
The value will only ever be an estimate because:
- it's possible for a single ticket to be added to multiple VSPs.
- vspd does not distinguish between immature and live tickets, whereas `getblockheader` only reports live tickets.
- `getblockheader` is reporting the size of the ticket pool as of the previous block, not the current block.
* xaur suggestions
* Show missed ticket %, not just the raw number.
- Fee tx status is now tracked using a dedicated field, with values none/received/broadcast/confirmed/error.
- Fee tx hex and hash are now both set in /payfee. The absense of txhash is no longer used to determine if a fee tx has been broadcast or not.
- setvotechoices can no longer be called before a fee is received.
- Remove `binding:required` from response types. It has no effect on responses, it is only needed on request types which are validated by gin.
