[UPD] Enforce C++ version and improve setup.py flexibility

Context

1. C++-14

Fixes aidge_core#225 (closed) for aidge_backend_cuda. The same update must be done on every module.

2. Python module compilation

Also increase setup.py compilation option flexibility using environment variables. Made to work with aidge!97 (merged)

unit_tests/Test_AvgPoolingImpl.cpp

@@ -236,8 +236,8 @@ TEST_CASE("[gpu/operator] AvgPooling(forward)", "[AvgPooling][GPU]")
             delete[] array0;
             cudaFree(array0_d);
         }
-        fmt::print("INFO: Number of elements over time spent: {}\n", number_of_operation / duration.count());
-        fmt::print("INFO: Total time: {}μs\n", duration.count());
+        Log::info("Number of elements over time spent: {}\n", number_of_operation / duration.count());
+        Log::info("Total time: {}μs\n", duration.count());
     }
 }