Update Language version to latest (#102)

* version 3.1.0

Signed-off-by: elvis ayiemba <7754523+ayiemba@users.noreply.github.com>

* Documentation urls modified

Signed-off-by: elvis ayiemba <7754523+ayiemba@users.noreply.github.com>

* Update reversal.md

* Update accountbalance.md

* Update b2b.md

* Update b2c.md

* Update callbacks.md

* Update callbacks.md

* Update callbacks.md

* Update and rename commonpitfalls.md to tips.md

* Update tips.md

* Update tips.md

* Update toc.yml

* Update index.md

* Update README.md

* Update README.md

* Update README.md

* Updated Documentation, resolved broken links

Signed-off-by: elvis ayiemba <7754523+ayiemba@users.noreply.github.com>

* updated documentation

Signed-off-by: elvis ayiemba <7754523+ayiemba@users.noreply.github.com>

* edited csproj

Signed-off-by: elvis ayiemba <7754523+ayiemba@users.noreply.github.com>

* Documentation

* Documentation

* Refactoring MpesaClient

* Adding test project

* version 3.1.3

* adding test project

* Update MpesaClient

* minor cleanup

* updates

* Improved Error Handling and Improved Asyn -> Sync conversion

* Adding Cancellation Tokens

* Update IMpesaClient.cs

* Update MpesaLib.csproj

* Update MpesaLib.csproj

src/MpesaLib/MpesaLib.csproj

@@ -16,6 +16,10 @@
     <IncludeBuildOutput>true</IncludeBuildOutput>   
     <Version>3.1.3</Version> 
   </PropertyGroup>
+
+  <PropertyGroup>
+    <LangVersion>latest</LangVersion>
+  </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|AnyCPU'">
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>