[doc] Improve documentation about C-c C-c to clear a transaction.
[doc] Improve documentation about C-c C-c to clear a transaction.

[ci skip]

afh/ledger,paulbdavis/ledger,ledger/ledger,ledger/ledger,jwakely/ledger,jwakely/ledger,jwakely/ledger,duncanmortimer/ledger,paulbdavis/ledger,duncanmortimer/ledger,duncanmortimer/ledger,jwakely/ledger,afh/ledger,ledger/ledger,paulbdavis/ledger,ledger/ledger,paulbdavis/ledger,duncanmortimer/ledger,afh/ledger,duncanmortimer/ledger,jwakely/ledger,afh/ledger,duncanmortimer/ledger,jwakely/ledger,paulbdavis/ledger,paulbdavis/ledger,duncanmortimer/ledger,afh/ledger,jwakely/ledger,ledger/ledger,paulbdavis/ledger