parser: add nowait keyword, add for update no wait grammar, and related error…#582

Merged

coocood merged 4 commits intopingcap:masterfrom cfzjywxk:nowait

Oct 18, 2019

+6,990-6,965

Commits on Oct 16, 2019

add nowait keyword, add for update no wait grammar, and related error code/msg
cfzjywxk
committed

Commits on Oct 17, 2019

move nowait to UnReservedKeyword
cfzjywxk
committed

Commits on Oct 18, 2019