Capability to ignore parsing emoji aliases inside url links

[fredericojssilva]

Description

Taking the following string as example:
hello :smiley:. The link is https://link_with_emoji_alias_:smiley:_that_we_do_not_want_to_replace

Currently parsing the above string to unicode will become:
hello 😃. The link is https://link_with_emoji_alias_😃_that_we_do_not_want_to_replace

Added a new method parseToUnicode(String input, boolean shouldIgnoreUrls) that will allow us to ignore the parsing inside urls.

The result will be a not broken link:
hello 😃. The link is https://link_with_emoji_alias_:smiley:_that_we_do_not_want_to_replace

[coveralls]

Coverage increased (+0.6%) to 93.842% when pulling 41070c3 on fredericojssilva:feature/ignore_alias_inside_urls into 8cf5fbe on vdurmont:master.

[vdurmont]

This looks good!

The URL regex probably won't catch all the cases though.
There are many discussions on the regexes for URLs: https://stackoverflow.com/questions/3809401/what-is-a-good-regular-expression-to-match-a-url

Maybe we should use a more complete one? What do you think?

[fredericojssilva]

@vdurmont agreed. Pushed a more complete one.

[fredericojssilva]

Hey @vdurmont. Have you had a chance to look at it?