* restore .gitmodules

* Revert "[TD-13408]<test>: move tests directory out"

This reverts commit 7db7bd9337cedc4cd0e3f3b16618b97d09791eaa.

* revert to make tests back

* immigrate file change in stand-alone repo to TDengine

* remove tests repository checkout
Co-authored-by: Ntangfangzhi <fztang@taosdata.com>

* [TD-13408]<test>: move tests directory out

* restore Jenkinsfile due to tests dir removal

* add --remote parameter to git submodule update

* git reset hard before checkout to branch

* call git submodule update for some submodules

* remove tests directory before checkout due to conflict

* as all branches remove tests, no need to remove it in script
Co-authored-by: Ntangfangzhi <fztang@taosdata.com>

* [TD-11518]<test>:add-csharp-sample-to-ci

* skip taosdemo

* fix conflict

* fix conflict 3rd

* [TD-11431]<feature>:c# connector publish and example fix

* update c# connector manual since connector publish to nuget

* fix doc,remove <feff>

* [TD-6535]<fix>: force cleanup tscCache to close tsc timer, which will cause segmentfault

* [TD-6543]<doc>: document support compile with dotnet sdk

* [TD-4944]:c# connector nanosecond support

* [TD-4944]:c# connector nanosecond support

* [TD-4944]:c# connector nanosecond support fix indent

* [TD-3877]<fix>: C# query result determination mechanism changed.

* [TD-3877]<fix>: C# query result determination mechanism changed.

change taosdemo and C#checker.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

Added unsigned integer types and change taosdemo insert and select queries for these types.

taos define | taos sql | c#
--- | --- | ---
UTINYINT | TINYINT UNSIGNED | `byte`
USMALLINT | SMALLINT UNSIGNED | `ushort`
UINT | INT UNSIGNED | `uint`
UBIGINT | BIGINT UNSIGNED | `ulong`
TINYINT | TINYINT | `sbyte`

Note: also change the tinyint value type to C# `sbyte`(the right signed one byte type) in this pr.

update README.md

support multithread create table and insertion.