1. Simplify implementation of taosHashCondTraverse
2. Complete function header comments for a few more functions

* Testing

Run through the sample mysql:
taos> create database db;
Query OK, 0 of 0 row(s) in database (0.002475s)

taos> use db;
Query OK, 0 of 0 row(s) in database (0.000252s)

taos> create table t (ts timestamp, a int);
Query OK, 0 of 0 row(s) in database (0.003588s)

taos> insert into t values ('2019-07-15 00:00:00', 1);
Query OK, 1 of 1 row(s) in database (0.001268s)

taos> insert into t values ('2019-07-15 01:00:00', 2);
Query OK, 1 of 1 row(s) in database (0.000265s)

taos> select * from t;
           ts            |      a      |
========================================
 2019-07-15 00:00:00.000 |           1 |
 2019-07-15 01:00:00.000 |           2 |
Query OK, 2 row(s) in set (0.000822s)

taos> drop database db;
Query OK, 0 of 0 row(s) in database (0.001711s)

1. Minor refactoring of taosHashInit
2. Complete error handling path of taosHashInit

* Testing
compile tdengine
cmake .. && cmake --build .

A few cleanups:
1. Move implementation details (macro definition, SHashEntry and SHashObj
   definition) to hash.c. Only leave relevant APIs in hash.h.
2. Complete function header comments.
3. Correct variable naming from "newSize" to "newCapacity".

A few cleanups:
1. Rename hash node "count" to "refCount" for ease of reading
2. Trailing white space removal of hash.h

A few cleanups for the hashtable implementation:
1. Correct function header comments
2. Complete argument checking for a few functions
3. Remove trailing space

[TS-676]<fix>: fixed coredump when 'group by' was used

[TS-636]<fix>:escape % with \ suport

insert datas contains multiple timestamp columns, but this tool transfer it to 'char' and pops up errors. (#8634)

* insert datas contains multiple timestamp columns, but this tool transfer it to 'char' and pops up errors.

* insert datas contains multiple timestamp columns, but this tool transfer it to 'char' and pops up errors.

* insert datas contains multiple timestamp columns, but this tool transfer it to 'char' and pops up errors.

[TS-561][TS-646]<test>: add test case

Test/td 10871 d

Release/ver 2.3.2.0

[TS-672]<doc>: update c sample code url for stmt

[td-10748]interp

Feature/d8

Feature/d7

merge from master into develop

merge from 2.0 into master

[TD-10965]<fix>:schemaless: some record can't write into TDengine by schemaless

[TD-10998]<fix>: set default JSON string type to nchar

because bug5903 has some error, comment  this case

<fix> fix the comPressMsgSize