Googlecpp Big O complexity benchmark not displayed in gh-pages

I have GoogleBenchmark's Big O complexity benchmark in my project which generates json:
```
{
"name": "coschedula::benchmarks::complexity::num_of_tasks_BigO",
"family_index": 10,
"per_family_instance_index": 0,
"run_name": "coschedula::benchmarks::complexity::num_of_tasks",
"run_type": "aggregate",
"repetitions": 1,
"threads": 1,
"aggregate_name": "BigO",
"aggregate_unit": "time",
"cpu_coefficient": 3.6672209291019148e-01,
"real_coefficient": 3.6674563409396432e-01,
"big_o": "N^2",
"time_unit": "ns"
}
```
It has different form then common benchmark output and action probably do not know hot to parse it and ends up with empty chart.

It would be good `big_o` field and `cpu_coefficient` or `real_coefficient` to be displayed on chart.