doc: Bump version in bips.md, mention bumping in release process

doc/bips.md

@@ -1,4 +1,4 @@
-BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.18.0**):
+BIPs that are implemented by Bitcoin Core (up-to-date up to **v0.19.0**):
 
 * [`BIP 9`](https://github.com/bitcoin/bips/blob/master/bip-0009.mediawiki): The changes allowing multiple soft-forks to be deployed in parallel have been implemented since **v0.12.1**  ([PR #7575](https://github.com/bitcoin/bitcoin/pull/7575))
 * [`BIP 11`](https://github.com/bitcoin/bips/blob/master/bip-0011.mediawiki): Multisig outputs are standard since **v0.6.0** ([PR #669](https://github.com/bitcoin/bitcoin/pull/669)).

doc/release-process.md

@@ -11,7 +11,7 @@ Release Process
 
 ### Before every major and minor release
 
-* Update [bips.md](bips.md) to account for changes since the last release.
+* Update [bips.md](bips.md) to account for changes since the last release (don't forget to bump the version number on the first line).
 * Update version in `configure.ac` (don't forget to set `CLIENT_VERSION_RC` to `0`).
 * Write release notes (see "Write the release notes" below).
 * Update `src/chainparams.cpp` nMinimumChainWork with information from the getblockchaininfo rpc.