allow setting transaction isolation#3102

Merged

sougou merged 3 commits intovitessio:masterfrom

HubSpot:tx_isolation

Aug 24, 2017

Commits on Aug 23, 2017

allow setting transaction isolation on vtgate session/executeoptions. enforce per-transaction before calling begin
bbeaudreault
committed
use a map for transaction isolation queries. use querypb
bbeaudreault
committed
merge conflicts
bbeaudreault
committed