consider add funlen as new rule

[jasonkylelol]

https://github.com/ultraware/funlen

[chavacava]

There are already some rules of that kind (eg line-length-limit) so why not.

[jasonkylelol]

it's different. line-length-limit warns when a line has characters over limit num. funlen warns when a function has too many lines.

[chavacava]

Hi @jasonkylelol, yes I understand that the goals of these rules are different, that's why I've said that I do not see any problem in adding that about function length.

[mgechev]

Sounds good to me.