* Fix a test timeout due to buggified knob MAX_WRITE_TRANSACTION_LIFE_VERSIONS
The buggified knob MAX_WRITE_TRANSACTION_LIFE_VERSIONS can be only 1M. In some
tests, this transaction always end up commitVersion - readVersion is a little
above 1M, thus always getting transaction_too_old error.
* Change MAX_COMMIT_BATCH_INTERVAL instead
So that the master may give out versions fast enough.
* Fix an assertion failure in a unit test
48125>>8 = 187, 48125 = 0xbbfd
48128>>8 = 188, 48128 = 0xbc00
So if 48125 is chosen as the index, 48128 changes the higher order byte.
48125 & 0xff7f = 47997 = 0xbb7d. Thus +5 won't change the higher order byte.
Jingyu Zhou