Extract TODO's

[ggwpez]

Location

Many *.go files.

Problem

TODO/BUG/FIXME should be removed from the code, the new linter is also not happy with them.

Proposal

We collect them here and triage so that i can remove them from the code.

client/sync.go // TODO cancel ongoing protocol, like Update
client/restore.go // TODO
client/update.go // TODO this is insecure after we sent our signature.
client/update.go // TODO how to handle invalid updates? Just drop and ignore them?
client/update.go // TODO how to handle invalid updates? Just drop and ignore them?
client/update.go // TODO this is insecure after we sent our signature.
wire/relay_test.go TODO waiting for mocked Endpoint
channel/persistence/statemachine_test.go // TODO After #316 (custom random gens) this test can be greatly improved.
watcher/local/watcher.go // TODO Should the subscription be closed with an error ?