ledger-mode: Add `ledger-remove-effective-date'.
ledger-mode: Add `ledger-remove-effective-date'.

Signed-off-by: Moritz Ulrich <2b469823646c02e9f01a7ad5b893ceac76b06bbe@tarn-vedra.de>

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