Update files.md for new wallets/ subdirectory

doc/files.md

@@ -6,13 +6,16 @@
 * blocks/rev000??.dat; block undo data (custom); since 0.8.0 (format changed since pre-0.8)
 * blocks/index/*; block index (LevelDB); since 0.8.0
 * chainstate/*; block chain state database (LevelDB); since 0.8.0
-* database/*: BDB database environment; only used for wallet since 0.8.0
+* database/*: BDB database environment; only used for wallet since 0.8.0; moved to wallets/ directory on new installs since 0.16.0
-* db.log: wallet database log file
+* db.log: wallet database log file; moved to wallets/ directory on new installs since 0.16.0
 * debug.log: contains debug information and general logging generated by bitcoind or bitcoin-qt
 * fee_estimates.dat: stores statistics used to estimate minimum transaction fees and priorities required for confirmation; since 0.10.0
 * mempool.dat: dump of the mempool's transactions; since 0.14.0.
 * peers.dat: peer IP address database (custom format); since 0.7.0
-* wallet.dat: personal wallet (BDB) with keys and transactions
+* wallet.dat: personal wallet (BDB) with keys and transactions; moved to wallets/ directory on new installs since 0.16.0
+* wallets/database/*: BDB database environment; used for wallets since 0.16.0
+* wallets/db.log: wallet database log file; since 0.16.0
+* wallets/wallet.dat: personal wallet (BDB) with keys and transactions; since 0.16.0
 * .cookie: session RPC authentication cookie (written at start when cookie authentication is used, deleted on shutdown): since 0.12.0
 * onion_private_key: cached Tor hidden service private key for `-listenonion`: since 0.12.0
 * guisettings.ini.bak: backup of former GUI settings after `-resetguisettings` is used