URI handling

[iTakeshi]

Fixes #46

Parentheses in URI

• ( and ) in a URI should be paired, otherwise they are removed from the match. This fixes the markdown link problem like [link](https://example.com) --- which is previously matched as https://example.com) but now it's correctly matched as https://example.com.
• On the other hand, matched parentheses in a URI can be detected, like https://en.wikipedia.org/wiki/WWW_(disambiguation).
• NOTE: This regex cannot detect nested parentheses. IMO it's acceptable for daily normal usecases.

Trailing periods/commas in URI

• In a sentence like Refer to the doc: https://doc.example.com/index.html., the regex detect the URI as https://doc.example.com/index.html. with the trailing period, leading us to the 404 page.
• I couldn't find a sophisticated way to detect/remove such trailing periods (note: lookaround is not what we want here) thus I wrote a small snippet to remove periods and commas in C code.

[endaaman]

@iTakeshi
CI somehow failed and I updated CI rules (upgrading to 22.04 from 20.04), so can you rebase PR branch and force-push?

[iTakeshi]

Sorry for my late response. I've force pushed the branch but there still remains an error which reads "Could not find a usable config.yml, you may have revoked the CircleCI OAuth app. Please sign out of CircleCI and log back in with your VCS before triggering a new pipeline."
Is this a problem on my side, or can you fix it?

[endaaman]

Sorry, this is my matter and I revoked and reauthorized third-patry app, then it has been fixed maybe.
Anyway, this PR is tested on my local machine and it's OK. merge.