Overhaul the IRC implementation.

* Simplified UI plumbing.
* Improves handling of errors and kicks.
* Persists chat history between session.
* Fixes leaks of the old widget tree when exiting.
* A few small UI polish improvements.

OpenRA.Mods.Common/OpenRA.Mods.Common.csproj

@@ -78,9 +78,6 @@
       <HintPath>..\thirdparty\download\ICSharpCode.SharpZipLib.dll</HintPath>
       <Private>False</Private>
     </Reference>
-    <Reference Include="SmarIrc4net">
-      <HintPath>..\thirdparty\download\SmarIrc4net.dll</HintPath>
-    </Reference>
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\OpenRA.Game\OpenRA.Game.csproj">
@@ -601,8 +598,6 @@
     <Compile Include="Widgets\Logic\Installation\DownloadPackagesLogic.cs" />
     <Compile Include="Widgets\Logic\Installation\InstallLogic.cs" />
     <Compile Include="Widgets\Logic\Installation\InstallMusicLogic.cs" />
-    <Compile Include="Widgets\Logic\IrcLogic.cs" />
-    <Compile Include="Irc.cs" />
     <Compile Include="Widgets\Logic\Lobby\ClientTooltipLogic.cs" />
     <Compile Include="Widgets\Logic\Lobby\KickClientLogic.cs" />
     <Compile Include="Widgets\Logic\Lobby\KickSpectatorsLogic.cs" />
@@ -707,6 +702,7 @@
     <Compile Include="Traits\World\MusicPlaylist.cs" />
     <Compile Include="Scripting\Global\LightingGlobal.cs" />
     <Compile Include="Traits\SupportPowers\ProduceActorPower.cs" />
+    <Compile Include="Widgets\Logic\GlobalChatLogic.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <PropertyGroup>