We store a blockheight at which point a private key is created, allowing
us to skip merkle checks before that time.
This was was tricky for a not yet synched wallet because its blockchain
was stuck at height zero.
Causing us to sync everything anyway.
Now we store the timestamp of wallet create instead, until the time that
the blockchain is synched. After that we resolve the block that we need
to start sync from based on that timestamp.
* Move colon out of translation
* Use the plural feature
this allows us to provide two translations for 1 or more items.
* Misc issues and inconsistencies fixed