Fix creation of the first chunk in an empty LSM tree: wait on the first update operation.

refs #1391, #1392
lsm_cursor.c:28: warning: 'primary' may be used uninitialized in this function
Cache all data handles in the session cache.

refs #1391
Ensure the read only flag is set in time for LSM.

Otherwise we can wait forever doing a read on an empty LSM tree.
Fix a deadlock involving eviction: don't block on the handle lock, and don't have exclusive operations drop and reacquire the handle list lock.

refs #1385, #1391, #1392