Merge pull request emacs-php#541 from emacs-php/release/1.21.4

Release 1.21.4

Merge pull request emacs-php#537 from emacs-php/release/v1.21.3

Release v1.21.3

Merge pull request emacs-php#511 from emacs-php/release/v1.21.2

Release v1.21.2

Bump version 1.20.1

Merge pull request emacs-php#495 from emacs-php/release/1.21.0

Release 1.21.0

Merge pull request emacs-php#487 from emacs-php/release/1.20.0

Release 1.20.0

Bump version 1.19.1, last version supporting Emacs 24.3 and earlier

GitHub-Issue: emacs-php#464
emacs-php#464

[Version] Bump version 1.19.0

Merge pull request emacs-php#395 from ejmr/release/v1.18.4

Release v1.18.4

[Version] Bump the version to v1.18.3 due to recent bug fixes

Signed-off-by: Eric James Michael Ritz <ericjmritz@yandex.com>