prepare release

update the 1.5.4 release date in the readme

Merge pull request j4mie#318 from j4mie/develop

Document the raw_execute() method

Merge pull request j4mie#310 from j4mie/develop

Merge develop into master for release

Add note about fixes to changelog

Add release date

Issue j4mie#156 findMany() returns only the last record in a set

Tag version 1.4.0

Tag version 1.3.0

Tag release 1.2.3