Update core, release version, and minor docs updates (#328)

Fixes #327
Fixes #321

Directory.Build.props

@@ -17,7 +17,7 @@
   </PropertyGroup>
 
   <PropertyGroup>
-    <Version>1.2.0</Version>
+    <Version>1.3.0</Version>
     <!--
       .NET does not allow the above version format for AssemblyVersion, and this
       is the version used in gRPC headers. The format is
@@ -32,7 +32,7 @@
       and 0.2.0 then is 0.2.0.5. But if there is no prerelease version, just
       leave revision off.
     -->
-    <AssemblyVersion>1.2.0</AssemblyVersion>
+    <AssemblyVersion>1.3.0</AssemblyVersion>
   </PropertyGroup>
 
   <ItemGroup>

README.md

@@ -706,6 +706,8 @@ with .NET tasks inside of workflows:
   * Use `Workflow.WhenAllAsync` instead.
   * Technically `Task.WhenAll` is currently deterministic in .NET and safe, but it is better to use the wrapper to be
     sure.
+* Do not use `CancellationTokenSource.CancelAsync`.
+  * Use `CancellationTokenSource.Cancel` instead.
 * Do not use `System.Threading.Semaphore` or `System.Threading.SemaphoreSlim` or `System.Threading.Mutex`.
   * Use `Temporalio.Workflows.Semaphore` or `Temporalio.Workflows.Mutex` instead.
   * _Technically_ `SemaphoreSlim` does work if only the async form of `WaitAsync` is used without no timeouts and

src/Temporalio/Client/RpcOptions.cs

@@ -27,7 +27,8 @@ public class RpcOptions : ICloneable
         public IReadOnlyCollection<KeyValuePair<string, string>>? Metadata { get; set; }
 
         /// <summary>
-        /// Gets or sets the timeout for the call. Default is no timeout.
+        /// Gets or sets the timeout for the call. Default timeout is specific to the call (for
+        /// normal calls this may be 30s, for long-poll calls it is longer).
         /// </summary>
         public TimeSpan? Timeout { get; set; }