Merge #52: Release tracking PR - v.0.19.2-0.4.1

b75d415 Add changelog for version bump v.0.19.2-0.4.1 (Tobin C. Harding)

Pull request description:

  We already did the version bump in #51, woops. Add changelog notes ready for release.

ACKs for top commit:
  apoelstra:
    ACK b75d415

Tree-SHA512: 5df20873c73175850275b6c08ae42dccef228d3b8cc7a4b07368d5c6fffbd2ab4cb28f22c4ac8d46177bb249fbc4f37973017498aa3b885a80c7655668f5318d

Author: apoelstra

CHANGELOG.md

@@ -1,3 +1,8 @@
+## v0.19.2-0.4.1
+
+* switch to using a git subtree for the bitcoin core code
+* vendor bitcoin core v0.19.2
+
 ## v0.19.0-0.4.0
 
 The major change in this version is the Minimum Supported Rust Version (MSRV) bump, we now support