[C++] Vendor uriparser library

[asfimport]

The uriparser C library is used internally for URI parsing. Instead of having an explicit dependency, we could simply vendor it.

Reporter: Antoine Pitrou / @pitrou
Assignee: Antoine Pitrou / @pitrou

PRs and other links:

• GitHub Pull Request #5865

_{Note: This issue was originally created as ARROW-7169. Please see the migration documentation for further details.}

[asfimport]

Antoine Pitrou / @pitrou:
@nealrichardson This might ease the work for R a bit.

[asfimport]

Krisztian Szucs / @kszucs:
Issue resolved by pull request 5865
#5865