* [TD-3841]<fix>: getFloat methed get 0 when data value is null

* change jdbc driver version number

* change

* [TD-3841]<test>: test Mybatis query null value

* change

* [TD-3906]<fix>: taosdemo back to 4 INT columns.

* [TD-3906]<fix>: taosdemo back to 4 columns.

test case need change correspondingly.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [TD-3880]<fix>: C# driver test miss unsigned type.

* [TD-3880]<fix>: C# driver test miss unsigned type.

also modify other files as what  TD-3204 did.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

for develop branch.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [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.

* [TD-3401]<fix>: taosdemo query statistic.

refactor func name.

* [TD-3401]<fix>: taosdemo query statistic.

refactor func name 2.

* [TD-3401]<fix>: taosdemo support query statistic.

implementation.

* cleanup
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

* [TD-3683]<fix>: reduce buffer size for more stable table creation.

* [TD-3683]<fix>: taosdemo create lots of tables.

clean up.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>

patch for master.
Co-authored-by: NShuduo Sang <sdsang@taosdata.com>