authn configs are checked independently per-auth provider,
this was to make authn providers more plugable.
in order to make environment variable overrides work for authn,
we need to have a unified view of the config layout,
no matter from root level, or partially checking per-provider
config independently, i.e. we try to use the same config envelop.
* feat: rewrite http api with hocon
* fix: crash when default_username is empty
* chore: udpate rewrite api with emqx_conf's cluster_rpc
* fix: spec wrong
* feat(emqx_conf): move conf manager for emqx_machine to emqx_conf
* chore(emqx_conf): change emqx:get_config/2 to emqx_conf:get/2
* fix: common test failed
* fix: badmatch by typo wrong key
* fix(emqx_conf): get the wrong core nodes
* fix(emqx_conf): get core node's tnx_id not latest tnx_id
* fix: add ro_transation when copy conf file
* fix: delete debug info
* fix: change ekka_rlog to mria_rlog
* fix: remove cluster_rpc from emqx_machine.
* fix: don't call ekka:start/0 explicitly
* fix: ekka should be start in emqx_machine
* feat: rewrite http api with hocon
* fix: crash when default_username is empty
* chore: udpate rewrite api with emqx_conf's cluster_rpc
* fix: spec wrong
* feat(emqx_conf): move conf manager for emqx_machine to emqx_conf
* chore(emqx_conf): change emqx:get_config/2 to emqx_conf:get/2
* fix: common test failed
* fix: badmatch by typo wrong key
* fix(emqx_conf): get the wrong core nodes
* fix(emqx_conf): get core node's tnx_id not latest tnx_id
* fix: add ro_transation when copy conf file
* fix: delete debug info
* fix: change ekka_rlog to mria_rlog
* fix: remove cluster_rpc from emqx_machine.
* fix: don't call ekka:start/0 explicitly
* fix: ekka should be start in emqx_machine