Qnx: Manage user debug token list

N.B: This patch implements the basic actions to manage user
debug tokens, and doesn't provide yet all actions and advanced
features available in Momentics IDE regarding the debug token support.

Change-Id: I912bdbcc3348b8ddd4335a7995bec900bd04bf62
Reviewed-by: Nicolas Arnaud-Cormos <nicolas@kdab.com>