Revise and generate msvc build-all commands.

Author: evoskuil

builds/msvc/build/build_all.bat

@@ -0,0 +1,7 @@
+@ECHO OFF
+CALL nuget_all.bat
+ECHO.
+CALL build_base.bat vs2017 libbitcoin-network "Microsoft Visual Studio\2017\Community\VC\Auxiliary\Build"
+CALL build_base.bat vs2015 libbitcoin-network "Microsoft Visual Studio 14.0\VC"
+CALL build_base.bat vs2013 libbitcoin-network "Microsoft Visual Studio 12.0\VC"
+PAUSE

builds/msvc/build/buildall.bat

@@ -0,0 +1,12 @@
+@ECHO OFF
+ECHO Downloading libbitcoin vs2017 dependencies from NuGet
+CALL nuget.exe install ..\vs2017\libbitcoin-network\packages.config
+CALL nuget.exe install ..\vs2017\libbitcoin-network-test\packages.config
+ECHO.
+ECHO Downloading libbitcoin vs2015 dependencies from NuGet
+CALL nuget.exe install ..\vs2015\libbitcoin-network\packages.config
+CALL nuget.exe install ..\vs2015\libbitcoin-network-test\packages.config
+ECHO.
+ECHO Downloading libbitcoin vs2013 dependencies from NuGet
+CALL nuget.exe install ..\vs2013\libbitcoin-network\packages.config
+CALL nuget.exe install ..\vs2013\libbitcoin-network-test\packages.config