Forwarding history

[JssDWt]

In this PR apis are added to fetch the forwarding revenue made per token.
The forwarding revenue comes for forwarding payments, not opening channels. So the fees that were charged for channel opens (which is in fact a routing fee) are excluded.
Forwards are associated to a token if the channel was opened with that token.
Forwarding revenue for a specific token can also be made if it's not us who has a channel to the user, but another LSP, and that LSP routed a payment through us. The external lsp can export its forwards associated with tokens, using the minimal necessary information. These forwards can then be imported to make them part of the revenue report. The external forwards are associated to local forwards to associate these local forwards to a token.

TODO:

• Give each forward a unique identifier to dedup.
• Make sure the channelpoint for cln is correct. Update if necessary.
• Create a server method to fetch revenue per api key.
• Figure out what to do with the channel backup and forwarding history backup
  • manually insert old/closed channels?
  • discuss whether it's ok to resync all this data
• test whether this setup gives the correct revenue per api key
• disallow creating a revenue report if the data hasn't been synced recently
• update glightning dependency
• indices in the database