Merge bitcoin#17026: doc: Update bips.md for default bech32 addresses in 0.20.0

fad1dbd doc: Fix amount typo in release notes (MarcoFalke)
fa8d052 doc: Update bips.md for default bech32 addresses in 0.20.0 (MarcoFalke)
fab68a0 doc: move-only release notes fragments for 0.20.0 (MarcoFalke)

Pull request description:

  * Restore release notes skeleton (headers)
  * Move-only all release notes fragments to the main file for 0.20.0
  * Update bips.md for the default bech32 address change

ACKs for top commit:
  fanquake:
    ACK fad1dbd

Tree-SHA512: c3d5e124fe803e809d5af869d89de2d8312d4481d43745c1492c66f5ffc6ffc9c37581cc9d8773d2fb711a5a4a47a12aa1ea31292ac6c393ef8503c9db053fc9

Author: fanquake

doc/bips.md

@@ -35,6 +35,6 @@ BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.19.0**):
 * [`BIP 152`](https://github.com/bitcoin/bips/blob/master/bip-0152.mediawiki): Compact block transfer and related optimizations are used as of **v0.13.0** ([PR 8068](https://github.com/bitcoin/bitcoin/pull/8068)).
 - [`BIP 158`](https://github.com/bitcoin/bips/blob/master/bip-0158.mediawiki): Compact Block Filters for Light Clients can be indexed as of **v0.19.0** ([PR #14121](https://github.com/bitcoin/bitcoin/pull/14121)).
 * [`BIP 159`](https://github.com/bitcoin/bips/blob/master/bip-0159.mediawiki): The NODE_NETWORK_LIMITED service bit is signalled as of **v0.16.0** ([PR 11740](https://github.com/bitcoin/bitcoin/pull/11740)), and such nodes are connected to as of **v0.17.0** ([PR 10387](https://github.com/bitcoin/bitcoin/pull/10387)).
-* [`BIP 173`](https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki): Bech32 addresses for native Segregated Witness outputs are supported as of **v0.16.0** ([PR 11167](https://github.com/bitcoin/bitcoin/pull/11167)).
+* [`BIP 173`](https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki): Bech32 addresses for native Segregated Witness outputs are supported as of **v0.16.0** ([PR 11167](https://github.com/bitcoin/bitcoin/pull/11167)). Bech32 addresses are generated by default as of **v0.20.0** ([PR 16884](https://github.com/bitcoin/bitcoin/pull/16884)).
 * [`BIP 174`](https://github.com/bitcoin/bips/blob/master/bip-0174.mediawiki): RPCs to operate on Partially Signed Bitcoin Transactions (PSBT) are present as of **v0.17.0** ([PR 13557](https://github.com/bitcoin/bitcoin/pull/13557)).
 * [`BIP 176`](https://github.com/bitcoin/bips/blob/master/bip-0176.mediawiki): Bits Denomination [QT only] is supported as of **v0.16.0** ([PR 12035](https://github.com/bitcoin/bitcoin/pull/12035)).

doc/release-notes-16524.md

@@ -63,6 +63,39 @@ distribution provides binaries for the RISC-V platform.
 Notable changes
 ===============
 
+New RPCs
+--------
+
+New settings
+------------
+
+Updated settings
+----------------
+
+Updated RPCs
+------------
+
+Note: some low-level RPC changes mainly useful for testing are described in the
+Low-level Changes section below.
+
+GUI changes
+-----------
+
+Wallet
+------
+
+- The wallet now by default uses bech32 addresses when using RPC, and creates native segwit change outputs.
+
+Low-level changes
+=================
+
+Tests
+-----
+
+- `-fallbackfee` was 0 (disabled) by default for the main chain, but 0.0002 by default for the test chains. Now it is 0
+  by default for all chains. Testnet and regtest users will have to add `fallbackfee=0.0002` to their configuration if
+  they weren't setting it and they want it to keep working like before. (#16524)
+
 Credits
 =======