FT-633 test case and bug fix for the data race between the lock request start and retry functions that results in a stall in the condition var broadcast

descriptor/ft_compare_func pair

abstractions and strengthen others, with an eye for simplicity and
consistency, not over-encapsulation.

git-svn-id: file:///svn/toku/tokudb@55577 c7de825b-a66e-492c-adef-691d508d4ae1

git-svn-id: file:///svn/toku/tokudb@55574 c7de825b-a66e-492c-adef-691d508d4ae1

git-svn-id: file:///svn/toku/tokudb@55567 c7de825b-a66e-492c-adef-691d508d4ae1

fixes #5961 pass a callback to the ydb layer when escalation occurs for a txnid, providing the locktree and range_buffer describing how to update the txn's internal data structures so they don't grow out of control for very long lived write transactions


git-svn-id: file:///svn/toku/tokudb@52941 c7de825b-a66e-492c-adef-691d508d4ae1

fixes #5351 fixes #5528 merge the new locktree to main. the locktree, locktree manager, and blocking lock request api are implemented at the toplevel under locktree/ and the ydb layer has been modified to use the new API. some kruft has been deleted from various parts of the source tree and these merge also includes a change where we kill 'includes.h'


git-svn-id: file:///svn/toku/tokudb@49851 c7de825b-a66e-492c-adef-691d508d4ae1