Updated slack APIs.

[dblock]

• Removed deprecated oauth_token, and leftover traces of channels and groups APIs.
• Added admin_auth_policy_assignEntities, admin_auth_policy_getEntities and admin_auth_policy_removeEntities admin_conversations_disconnectShared, admin_users_session_clearSettings, admin_users_session_getSettings, admin_users_session_resetBulk, admin_users_session_setSettings, apps_manifest_create, apps_manifest_delete, apps_manifest_export, apps_manifest_update, apps_manifest_validate, conversations_acceptSharedInvite, conversations_approveSharedInvite, conversations_declineSharedInvite, conversations_inviteShared, conversations_listConnectInvites, oauth_v2_exchange, openid_connect_token, openid_connect_userInfo, team_billing_info, team_preferences_list, tooling_tokens_rotate.
• Incremented version to 1.0.