add buildall script for mono

csharp/buildall.sh

+#!/bin/bash
+# Use mono to build solution and run all tests.
+
+# Adjust these to reflect the location of nunit-console in your system.
+NUNIT_CONSOLE=nunit-console
+
+# The rest you can leave intact
+CONFIG=Release
+KEYFILE=../keys/Google.ProtocolBuffers.snk  # TODO(jtattermusch): signing!
+SRC=$(dirname $0)/src
+
+set -ex
+
+echo Building the solution.
+xbuild /p:Configuration=$CONFIG $SRC/ProtocolBuffers.sln
+
+echo Running tests.
+$NUNIT_CONSOLE $SRC/ProtocolBuffers.Test/bin/$CONFIG/Google.ProtocolBuffers.Test.dll
+
+$NUNIT_CONSOLE $SRC/ProtocolBuffersLite.Test/bin/$CONFIG/Google.ProtocolBuffersLite.Test.dll
+
+$NUNIT_CONSOLE $SRC/ProtocolBuffersLite.Test/bin/$CONFIG/Google.ProtocolBuffersMixedLite.Test.dll