Add top level stringToInput sender in header

This is the same for all platforms, so thers' no reason to duplicate it
in platform specific sections.

src/keyboard_input/input_sender.h

@@ -9,3 +9,10 @@ enum class KeyStatus
 };
 
 void sendTokensAsInput( const std::vector<Token> tokens );
+
+void sendStringAsInput( const std::string input )
+{
+    const auto tokens = ParseKeyboardInputsToTokens( input );
+    const auto inputs = removeIncorrectTokens( tokens );
+    sendTokensAsInput( inputs );
+}