0! [SECURITY] Drop privilegies. Preserve access to files via "capabilities".
1. Remove pthreads metainfo GC
2. Replace g_hash_table* with "tsearch" and so on.
3. Remove all code with "#ifdef DOXYGEN"
4. Find-out is "pthread_tryjoin_np()" really required? Can we remove all this
	"threadsinfo" mechanism?

	There's a memleak if not pthread_*join*() is done.

5. Deduplicate code from functions, that calls sync_exec() and sync_exec_thread()
6. Fix variables' names
7. [CLUSTER] Replace node_id value with his ipv4 address (8bits -> 32bits)
8. In daemon mode stdout/stderr should be redirected to system log.