Remove obsolete MSVC stuff.

c++/msvc/capnproto.sln

-
-Microsoft Visual Studio Solution File, Format Version 12.00
-# Visual Studio 14
-VisualStudioVersion = 14.0.22310.1
-MinimumVisualStudioVersion = 10.0.40219.1
-Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "capnproto", "capnproto.vcxproj", "{CD7EEDAE-3D48-4402-9F60-EC23311BE143}"
-EndProject
-Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "gtest", "..\gtest\msvc\gtest.vcxproj", "{C8F6C172-56F2-4E76-B5FA-C3B423B31BE7}"
-EndProject
-Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "gtest_main", "..\gtest\msvc\gtest_main.vcxproj", "{3AF54C8A-10BF-4332-9147-F68ED9862032}"
-EndProject
-Global
-	GlobalSection(SolutionConfigurationPlatforms) = preSolution
-		Debug|Win32 = Debug|Win32
-		Release|Win32 = Release|Win32
-	EndGlobalSection
-	GlobalSection(ProjectConfigurationPlatforms) = postSolution
-		{CD7EEDAE-3D48-4402-9F60-EC23311BE143}.Debug|Win32.ActiveCfg = Debug|Win32
-		{CD7EEDAE-3D48-4402-9F60-EC23311BE143}.Debug|Win32.Build.0 = Debug|Win32
-		{CD7EEDAE-3D48-4402-9F60-EC23311BE143}.Release|Win32.ActiveCfg = Release|Win32
-		{CD7EEDAE-3D48-4402-9F60-EC23311BE143}.Release|Win32.Build.0 = Release|Win32
-		{C8F6C172-56F2-4E76-B5FA-C3B423B31BE7}.Debug|Win32.ActiveCfg = Debug|Win32
-		{C8F6C172-56F2-4E76-B5FA-C3B423B31BE7}.Debug|Win32.Build.0 = Debug|Win32
-		{C8F6C172-56F2-4E76-B5FA-C3B423B31BE7}.Release|Win32.ActiveCfg = Release|Win32
-		{C8F6C172-56F2-4E76-B5FA-C3B423B31BE7}.Release|Win32.Build.0 = Release|Win32
-		{3AF54C8A-10BF-4332-9147-F68ED9862032}.Debug|Win32.ActiveCfg = Debug|Win32
-		{3AF54C8A-10BF-4332-9147-F68ED9862032}.Debug|Win32.Build.0 = Debug|Win32
-		{3AF54C8A-10BF-4332-9147-F68ED9862032}.Release|Win32.ActiveCfg = Release|Win32
-		{3AF54C8A-10BF-4332-9147-F68ED9862032}.Release|Win32.Build.0 = Release|Win32
-	EndGlobalSection
-	GlobalSection(SolutionProperties) = preSolution
-		HideSolutionNode = FALSE
-	EndGlobalSection
-EndGlobal

c++/msvc/gen-test-code.bat

-@echo off
-
-rem You'll need to build capnp.exe and capnpc-c++.exe using MinGW.
-
-capnp compile -oc++ -I../src --src-prefix=../src ../src/capnp/test.capnp ../src/capnp/test-import.capnp ../src/capnp/test-import2.capnp

c++/msvc/readme.txt

-MSVC project files
-
-As of this writing, this MSVC project is very basic: all it does is compile a
-unit test covering all lite-mode functionality. In the long run, we intend for
-MSVC libraries to be compiled using the cmake files. This project is a stopgap
-because Kenton doesn't understand cmake and wanted to get some work done.
-
-The solution file refers to gtest, which must be downloaded to "c++/gtest".
-The "setup-autotools.sh" script accomplishes this, although it requires bash
-to run.
-
-The solution also refers to generated code for test schemas which should be
-under msvc/capnp (i.e. a directory called "capnp" within *this* directory).
-To generate these files, do the following:
-
-1. Build capnp.exe and capnpc-c++.exe with MinGW. (Or, download the
-   precompiled binaries if they are available.)
-2. Copy those files to this directory, or somewhere in PATH.
-3. Run gen-test-code.bat.