Modify end_tag_regex to allow named arrays

[michaelalandawson]

When determining if a custom tag uses an end tag, the regex should also allow for the following:

thistag["executionmode"] thistag['executionmode']

Currently, the regex only allows for thistag.executionmode to determine the end tag.

The proposed regex was tested with the following variations:

thistag.executionmode == "end" thistag.executionmode == 'end' thistag.executionmode eq "end" thistag.executionmode eq 'end' thistag.executionmode is "end" thistag.executionmode is 'end' thistag["executionmode"] == "end" thistag["executionmode"] == 'end' thistag["executionmode"] eq "end" thistag["executionmode"] eq 'end' thistag["executionmode"] is "end" thistag["executionmode"] is 'end' thistag['executionmode'] == "end" thistag['executionmode'] == 'end' thistag['executionmode'] eq "end" thistag['executionmode'] eq 'end' thistag['executionmode'] is "end" thistag['executionmode'] is 'end'

Thank you!