Use custom cookiejar to prevent JSESSIONID errors

[ahuret]

Hi !

This PR fix rundeck's bug about JSESSIONID, currently rundeck doesn't allow api clients to get multiple sessions for the same user (but it should as mentionned in https://docs.rundeck.com/docs/administration/configuration/configuration-file-reference.html - see rundeck.security.maxSessions parameter).

When AuthMethod is "token", it inject TokenAuthCookieJar as http.CookieJar and then remove JSESSIONID cookies from request.

Same workaround has been implemented in official rundeck golang api (https://github.com/rundeck/go-rundeck/commit/38df8401023e7d1fa635d0eda9db6eca5d08ec8f)