luaconfig: Fixed LogWriterOptions parsing.

Certain options was taken from wrong index of stack.
luasource: Added signallable sleep.

Sleep function in lua source should be interruptible by outer conditions.
(Like shutting down the source).
luasource: We should honor the window limits.

Luasource didn't check the state of the window, this led to
nasty race conditions. Now, we are checking for the window state,
and going to sleep, if there is no free slot available in the window.
Wakeup mechanism is also implemented.
luaconfig: Added Parser and DBParser bindings.