Dropped php7.1 and 7.2 updated some packages. (#321) * removed travis-ci and added github actions build status to readme Signed-off-by: fenn-cs <[email protected]> * added php 8 to ci, updated build name Signed-off-by: fenn-cs <[email protected]> * added alternate php versions Signed-off-by: fenn-cs <[email protected]> * dropped php7.0, php7.1, updated jms/serializer Signed-off-by: fenn-cs <[email protected]>