Revert "Use singleton lock in LFGMgr v0.2. move LFG structures to singleton. must give some speedup and safety, but need test (dangerows!)"

This reverts commit a7ba60c448ce546535565a2d1465b8a6c44e9068.
Use singleton lock in LFGMgr v0.3. move LFG structures to singleton. must give some speedup and safety, but need test (dangerows!)