Support changing the wait time of a running fridge

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Swallow LRU

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Swallow the Reaper.

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Clean up no longer used stuff

Specifically get rid of the pthread_ts for things that are now in a
fridge, and bits of data related to the removed flusher threads (that
were part of the removed content cache.)

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Clean up some no-longer-used parameters

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Add per-thread initialize/finalizer and data

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Let looper processes do their own waiting

This model avoids infecting the loopers with the fridge's state
machine logic.  The fridge parameters provide the fridge with a
function that will wake all sleepers, and the fridge provide a
function, fridgethr_you_should_break that the function should call
before sleeping or doing work (and return if it's true.)

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Swallow the worker threads

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Remove TCB

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
State Destroyer WIP