feat: ILP Auth, TSL transport, Async API

Author: bluestreak01

README.md

@@ -5,25 +5,71 @@
 - Basic usage
 
 ```c#
-using var ls = new LineTcpSender(IPAddress.Loopback.ToString(), 9009);
+using var ls = await LineTcpSender.ConnectAsync("localhost", 9009, tlsMode: TlsMode.Disable);
 ls.Table("metric_name")
     .Symbol("Symbol", "value")
-    .Colum("number", 10)
-    .Colum("double", 12.23)
-    .Colum("string", "born to shine")
+    .Column("number", 10)
+    .Column("double", 12.23)
+    .Column("string", "born to shine")
     .At(new DateTime(2021, 11, 25, 0, 46, 26));
-ls.Flush();
+await ls.SendAsync();
 ```
 
 - Multi-line send
 
 ```c#
-using var ls = new LineTcpSender(IPAddress.Loopback.ToString(), 9009);
+using var ls = new LineTcpSender("localhost", 9009, tlsMode: TlsMode.Disable);
 for(int i = 0; i < 1E6; i++) 
 {
     ls.Table("metric_name")
-        .Colum("counter", i)
+        .Column("counter", i)
         .AtNow();
 }
-ls.Flush();
+ls.Send();
 ```
+
+- Authenticated
+```c#
+ using var ls = new LineTcpSender("localhost", 9009);
+ await ls.Authenticate("admin", "NgdiOWDoQNUP18WOnb1xkkEG5TzPYMda5SiUOvT1K0U=");
+ ls.Table("metric_name")
+    .Column("counter", i)
+    .AtNow();
+await ls.SendAsync();        
+``` 
+
+- Fixed IO Buffer size
+```c#
+ using var ls = new LineTcpSender("localhost", 9009, bufferOverflowHandling: BufferOverflowHandling.SendImmediately);
+ await ls.Authenticate("admin", "NgdiOWDoQNUP18WOnb1xkkEG5TzPYMda5SiUOvT1K0U=");
+ ls.Table("metric_name")
+    .Column("counter", i)
+    .AtNow();
+await ls.SendAsync();        
+``` 
+
+### Construction parameters
+
+| Name                     | Default      | Description                                                                                                                                                                                                                                | 
+|--------------------------|--------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| 
+| `host`                   |              | Host or IP address of QuestDB server                                                                                                                                                                                                       |
+| `port`                   |              | QuestDB Port. Default ILP port is 9009                                                                                                                                                                                                     |
+| `bufferSize`             | 4096         | Default send buffer size                                                                                                                                                                                                                   |
+| `bufferOverflowHandling` | `Extend`  | There are 2 modes: <br/> - `Extend` will grow input buffer until `Send()` or `SendAsync()` method called<br/> - `SendImmediately` will no extend the IO Buffer and automatically executes `Send()` immediatly when IO Buffer overflown     |
+| `tslMode`                | `Enable` | There are 3 TSL modes:<br/>- `Enable`. TLS is enabled, sever certificate is checked<br/> - `AllowAnyServerCertificate`. TLS enabled, server certificate is not checked<br/>- `Disable`                                                     |
+
+### Properties and methods
+
+| Name                                                                 | Description                                                                                                    |
+|----------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------|
+| `AuthenticateAsync(string keyId, string privateKey)`                 | Authenticates with QuestDB certificates                                                                        |
+| `Table(string name)`                                                 | Starts new line from table name                                                                                |
+| `Symbol(string sybolName, string value)`                             | Symbol column value                                                                                            |
+| `Column(stirng columnName, string / long / double / DateTime value)` | Column name and value                                                                                          |
+| `At(DateTime / long timestamp)`                                      | Designated timestamp for the line                                                                              | 
+| `AtNow()`                                                            | Finishes line leaving QuestDB sever to set the timestamp                                                       |
+| `Send() / SendAsync() `                                              | Send IO Buffers to QuestDB                                                                                     |
+| `CancelLine()`                                                       | Cancels current line. Works only when `bufferOverflowHandling` set to `Extend`                                 |
+| `TrimExcessBuffers()`                                                | Trims empty buffers used to grow IO Buffer. Only useful when `bufferOverflowHandling` set to `Extend`          | 
+| int `WriteTimeout`                                                   | Value, in milliseconds, that determines how long the underlying stream will attempt to write before timing out |
+| `IsConnected`                                                        | Indicates if the connection to QuestDB open                                                                    |