New "subword" text object will treat -, _ as delimiters and operates on parts of camelCase

[nik-rev]

This is a text object like iw but it also treats _, - as word delimiters and operater only on a part of camelCase.

Examples, with cursor at *:

before	command	after
longCa*melCase	mird	longCase
l*ongCamelCase	mird	CamelCase
longCa*melCase	mard	longCase
long_s*nake_case	mird	long__case
lo*ng_snake_case	mird	_snake_case
long_sn*ake_case	mard	snake_case
lo*ng_snake_case	mard	_snake_case
long_k*ebab_case	mird	long--case
lo*ng_kebab_case	mird	-snake-case
long_ke*bab_case	mard	long-case
lo*ng_kebab_case	mard	-kebab-case

Otherwise, it will act just like iw or aw

The choice to use r to represent this textobject is arbitrary and can be changed