* Refactor API to be able to handle managed modules
 * Deprecate much of old p11-kit API
 * Implement concept of managed modules
 * Make C_CloseAllSessions function work for multiple callers
 * New dependency on libffi
 * Fix possible threading problems reported by hellgrind
 * Add log-calls option
 * Mark p11_kit_message() as a stable function
 * Use our own unit testing framework