FIX change endpoint to post member and fix roles parsing

[benoitLebreton-perso]

Description

Hello,

on the doccano version I'm currently using (it must but 1.8.0 the latest)

the post of a member must have changed (role and user insted of id,role,rolename,user,username)

also the parsing of the roles role_info["name"] instead of role_info["rolename"]

Have a look and have a nice day

[houssam7737]

So quite a few other endpoints have changed between the client (which I believe supports 1.5 right now) and the latest doccano version. I think moving forward the plan is to update the beta-client to support newer and newer version of doccano, with the right semver versioning. Currently the beta-client supports 1.5, and there is a PR out to support 1.7. I don't know if that client also supports 1.8 or if doccano 1.8 introduced some other backwards incompatible changes. If not, the next step is to support 1.8. You're welcome to open a PR and contribute :) Just a heads up I think you will need to update a few more endpoints. See the code under beta/

[Hironsan]

close due to the duplication https://github.com/doccano/doccano-client/pull/73