added a timeout parameter to connection_pool::acquire and a connection_pool::try_acquire with connection id

include/matador/sql/connection_pool.hpp

@@ -4,6 +4,7 @@
 #include "matador/sql/connection.hpp"
 #include "matador/sql/connection_info.hpp"
 
+#include <chrono>
 #include <condition_variable>
 #include <mutex>
 #include <string>
@@ -11,7 +12,6 @@
 #include <unordered_map>
 
 namespace matador::sql {
-
 class connection_pool;
 
 struct identifiable_connection {
@@ -49,7 +49,8 @@ public:
 
   connection_ptr acquire();
   connection_ptr try_acquire();
-  connection_ptr acquire(size_t id);
+  connection_ptr try_acquire(size_t id);
+  connection_ptr acquire(size_t id, std::chrono::milliseconds timeout = std::chrono::milliseconds(5000));
 
   void release(identifiable_connection *c);
   void release(connection_ptr &c);