Swallow the worker threads

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

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

Add functionality to break down the inode cache, closing file
descriptors, and relasing state in the FSAL.  This is all done without
taking any locks so that the shutdown procedure doesn't hang in the
event of a thread being cancelled while holding a lock.

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Fix a bug in VFS/PanFS

Missing semicolon.

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Shut down and release FSAL resources

This is not done locklessly.  Since there's so much locking done in
the FSAL on release, I didn't want to mess with it.  I'd propose we
add a flag that we can pass to the release methods to bypass locking.

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Add thread list

Signed-off-by: Adam C. Emerson <aemerson@linuxbox.com>
Thread Cancellation

Implement support for cancelling threads and change the major subsystems
to use it on timeout.

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