Make touch regex configurable

[mikehaertl]

I'd like to supress autoclose not only for alphanum characters to the right of the cursor. This could be easily achieved if the %w regex here would be configurable:

autoclose.nvim/lua/autoclose.lua

Lines 106 to 107 in a9ecd7e

	config.options.disable_when_touch
	and (pair .. "_"):sub(2, 2):match("%w")

[m4xshen]

Add touch_regex option in fb1530a. Thanks for the feedback!