LSM configuration and thread management changes to lay the foundation
for dynamic LSM threads. #1237
Add reconfigure support for LSM manager #1237
Fix which half of LSM workers can handle merges. #1247
Decrement lsm_workers. #1237
Merge branch 'develop' into lsm-threads

Conflicts:
	src/lsm/lsm_manager.c
Fix unused var warnings.
Merge pull request #1248 from wiredtiger/lsm-threads

Support reconfigure of LSM manager/worker threads.