Added mutex lock to log output.

Log.cpp

@@ -61,6 +61,8 @@ namespace coreutils {
    Log::~Log() {
       
       if(output) {
+
+	 mtx.lock();
 	 
 	 std::stringstream out;
 	 out << seq << "." << this->str() << std::endl;;
@@ -73,6 +75,8 @@ namespace coreutils {
 	 
 	 std::cout << out.str();
 	 ++seq;
+	 
+	 mtx.unlock();
       }
    }