avoid infinite loop in _BufBuilder::grow_reallocate #1007

fixes #1007
made lock context non-default and fixed two usages of it #1008
fixed tests that didn't have lock contexts #1008

fixes #1008
changed dumpCrashInfo to catch all exceptions inside it #1009

fixes #1009
Merge branch 'bugfixes/tokumx-1.4' into releases/tokumx-1.4