Improve quoting behavior when launching procs with cmd.exe

Using /S and quotes is better than no S and parens because the parens can get tripped up when > operator is used (since > has higher precedence than parens)

src/cpp/core/system/Win32ChildProcess.cpp

@@ -261,8 +261,9 @@ void ChildProcess::init(const std::string& command,
                         const ProcessOptions& options)
 {
    exe_ = findOnPath("cmd.exe");
+   args_.push_back("/S");
    args_.push_back("/C");
-   args_.push_back("(" + command + ")");
+   args_.push_back("\"" + command + "\"");
    options_ = options;
 }
 

src/cpp/session/consoleio/ConsoleIOMain.cpp

@@ -296,7 +296,7 @@ int main(int argc, char** argv)
                                                   ::GetCommandLine());
 
    // Use cmd.exe to allow shell commands like "dir" to work properly
-   cmd = "cmd.exe /c (" + cmd + ")";
+   cmd = "cmd.exe /s /c \"" + cmd + "\"";
    std::vector<char> cmdBuf(cmd.size() + 1, '\0');
    cmd.copy(&(cmdBuf[0]), cmd.size());