Update TAOS SQL-ch.md

update the taos sql document.

replace grafana subscribe sql

[#1059 TBASE-1436]

[#issue-1057 TBASE-1433]

Update tscUtil.c

fix invalid release operatons

fix the invalid release operations when the database is dropped and the metermeta cache is cleaned up at the client side. #1053  [tbase-1435]

Update connector-ch.md

Update tscStream.c

fix bugs in #1047. [tbase-1434]

#1041

add dashboard json

[TBASE-816]

Feature/grafana plugin

[#1039 TBASE-816]

add the null-terminated char for binary data

correct typos in node.js connector chinese user guide

Update vnodeQueryImpl.c

add the null-terminated char for the binary data, if the space if available.

add statistic and save option

Feature/lihui