Fixed mssing virtual destructor warnings

In Visual Studio with warning 4265 enabled
Closes #844

include/internal/catch_impl.hpp

@@ -91,6 +91,7 @@ namespace Catch {
     TestSpec::NamePattern::~NamePattern() {}
     TestSpec::TagPattern::~TagPattern() {}
     TestSpec::ExcludedPattern::~ExcludedPattern() {}
+	Matchers::Impl::MatcherUntypedBase::~MatcherUntypedBase() {}
 
     void Config::dummy() {}
 

include/internal/catch_matchers.hpp

@@ -27,6 +27,7 @@ namespace Matchers {
             }
 
         protected:
+			virtual ~MatcherUntypedBase();
             virtual std::string describe() const = 0;
             mutable std::string m_cachedToString;
         private: