Update CHANGELOG.md

Update CHANGELOG.md

5.1.0 is going out

5.0.0 is going out

ABL

Merge pull request rqlite#551 from zmedico/client-ca-cert-option-4.3.0

Add rqlite -ca-cert option to specify trusted root CA certificate

Allow Raft election timeout to be set

Allow control of shutdown-on-remove

Defaults to leaving Raft run if the node is removed.

4.3.0 is going out

4.2.3 is going out