Feature-Request: customize name of columns added with "split cols" function

[fabiopipitone]

Hi there!

It'd be extremely helpful to customize the name of the column added with the split cols function.

In fact, if I decide to split the columns on a given field result which can be either SUCCESS or FAIL , I'll have two added columns named SUCCESS - Count and FAIL - Count.

Let's say I only want to keep the SUCCESS - Count column and rename it MY_COUNTS, it is not possible right now since the part linked to the "split cols" action (i.e. SUCCESS - and FAIL - in this case) is fixed and not editable.

It might be convenient to add a further option when split cols bucket is used.
Say custom split col label. When it is checked, you can customize col label, using handlebars syntax.
The default value would be : {{bucketValue}} - {{metricLabel}}, and could be customized as you wish.

In the above-mentioned example, one would change the metric label (using classic way) to MY_COUNTS and then set custom split col label to {{metricLabel}}.