Updated logic to support external links
Closes #3172497
Regex to find external links inspired from https://stackoverflow.com/questions/10687099/how-to-test-if-a-url-string-is-absolute-or-relative#answer-19709846
Closes #3172497
Regex to find external links inspired from https://stackoverflow.com/questions/10687099/how-to-test-if-a-url-string-is-absolute-or-relative#answer-19709846