frequency: add --other option

[jqnatividad]

When compiling frequency tables with the different limit options, give the user the option to create an "other" aggregation, summing up the other values beyond the limit, e.g. if we run frequency with the default limit of 10...

field,value,count
state,NY,100
state,NJ,70
state,CA,60
state,MA,55
state,FL,45
state,TX,43
state,NM,40
state,AZ,39
state,NV,38
state,MI,35
state,OTHER,250

[rzmk]

Another thing that may be useful is adding a flag to also add a column for the percentage/decimal based on the frequency/(total rows). Could maybe use qsv count for the total rows part.

[rzmk]

Also I'm curious how --other would handle if a value itself is named OTHER.

[jqnatividad]

The percentage option is a great idea. And for --other, maybe we can add another option called --other-text with a default value of OTHER. It should be easy to add some field value collision logic on the off chance a valid field value is OTHER.

[rzmk]

Maybe for --other it could be consolidated to --other <text> with default OTHER?

[jqnatividad]

Given @rzmk 's feedback, we'll add a percentage column:

field, value, count, percentage
state, NY, 100, 12.90
state, NJ, 70, 9.03
state, CA, 60, 7.74
state, MA, 55, 7.10
state, FL, 45, 5.81
state, TX, 43, 5.55
state, NM, 40, 5.16
state, AZ, 39, 5.03
state, NV, 38, 4.90
state, MI, 35, 4.52
state, OTHER (40), 250, 32.26

with the OTHER text being followed by the sum of other unique field values, enclosed in parentheses.