Indicate which sampler raises which error code and the number of errors raised.

[reda-idtaleb]

At present, we group errors by type and present them in a separate table. For each type of error, we also indicate the percentage among errors and the percentage among requests. But it's still difficult to know which sampler raises a specific type of error (especially for those listed in the table of top errors). We can therefore provide this information to simplify error analysis.
We can have a table listing for each sampler the error code raised and the number of errors raised by that sampler.

The table may look like :

Samplers	404	500	...
sample_1	20	20
sample_2	5	0
.....