Add Release Note (feature): Comes with the MSYS2 runtime (Git for Windows flavor) based on [Cygwin v3.5.6](https://inbox.sourceware.org/cygwin-announce/[email protected]/) (Git for Windows skipped [v3.5.5](https://inbox.sourceware.org/cygwin-announce/[email protected]) because it failed to pass Git's test suite).

Add Release Note (feature): Comes with the MSYS2 runtime (Git for Windows flavor) based on [Cygwin v3.5.6](https://inbox.sourceware.org/cygwin-announce/[email protected]/) (Git for Windows skipped [v3.5.5](https://inbox.sourceware.org/cygwin-announce/[email protected]) because it failed to pass Git's test suite). #163