make libsndfile compile as c and not c++ code in msvc

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@225 d0543943-73ff-0310-b7d9-9358b9ac24b2

w32/vsnet/Tools/libsndfile.vcproj

@@ -46,9 +46,10 @@
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
 				UsePrecompiledHeader="0"
-				WarningLevel="0"
+				WarningLevel="1"
 				Detect64BitPortabilityProblems="true"
 				DebugInformationFormat="4"
+				CompileAs="1"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"
@@ -107,9 +108,10 @@
 				PreprocessorDefinitions="WIN32;NDEBUG;_LIB;inline=__inline;_CRT_SECURE_NO_DEPRECATE;_CRT_NONSTDC_NO_DEPRECATE"
 				RuntimeLibrary="2"
 				UsePrecompiledHeader="0"
-				WarningLevel="0"
+				WarningLevel="1"
 				Detect64BitPortabilityProblems="true"
 				DebugInformationFormat="3"
+				CompileAs="1"
 			/>
 			<Tool
 				Name="VCManagedResourceCompilerTool"