Xamarin.Android.sln: Add required projects from external/Java.Interop

This is required because of a bug in xbuild. It tries to look for the
Java.Interop projects which are referenced from the other projects, in
the sln itself, because it needs to figure out a build order for *all*
the projects. It should probably allow projects not being present in sln
and build them via the reference.

Author: Ankit Jain

Xamarin.Android.sln

@@ -27,6 +27,18 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "api-merge", "build-tools\ap
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Mono.Android.Export", "src\Mono.Android.Export\Mono.Android.Export.csproj", "{B8105878-D423-4159-A3E7-028298281EC6}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Java.Interop.Tools.Cecil", "external\Java.Interop\src\Java.Interop.Tools.Cecil\Java.Interop.Tools.Cecil.csproj", "{D48EE8D0-0A0A-4493-AEF5-DAF5F8CF86AD}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Java.Interop.Tools.Diagnostics", "external\Java.Interop\src\Java.Interop.Tools.Diagnostics\Java.Interop.Tools.Diagnostics.csproj", "{64CC4E44-CE3A-4319-BF3F-6CF8BD513870}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Xamarin.Android.Tools.AnnotationSupport", "external\Java.Interop\src\Xamarin.Android.Tools.AnnotationSupport\Xamarin.Android.Tools.AnnotationSupport.csproj", "{07BC4495-1267-4B78-9EA6-B76FEEA2A64A}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Xamarin.Android.Tools.ApiXmlAdjuster", "external\Java.Interop\src\Xamarin.Android.Tools.ApiXmlAdjuster\Xamarin.Android.Tools.ApiXmlAdjuster.csproj", "{1268EADF-8344-431C-81F6-FCB7CBC99F49}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "jcw-gen", "external\Java.Interop\tools\jcw-gen\jcw-gen.csproj", "{52C7D9B6-E8C8-47D0-9471-652D278D7D77}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Java.Interop.Tools.JavaCallableWrappers", "external\Java.Interop\src\Java.Interop.Tools.JavaCallableWrappers\Java.Interop.Tools.JavaCallableWrappers.csproj", "{D18FCF91-8876-48A0-A693-2DC1E7D3D80A}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|AnyCPU = Debug|AnyCPU