Set presence information

A user can set their presence information by using the vx_req_account_set_presence message.

The following code displays an example of this process:

vx_req_account_set_presence_message   req;
vx_req_account_set_presence_message_create(&req);
req->account_handle = vx_strdup(".issuer-w-dev.mytestaccountname.");
req->presence = buddy_presence_busy;
req->custom_message = vx_strdup(“I am busy cleaning my keyboard.”);
vx_issue_request3(&req->base);