Backport org.apache.hc.core5.http.URIScheme to HC 4

[Gary Gregory]

Hi All:

I have to maintain code bases that use HCore 4 and HCore 5.

It would help some of my code look similar if I we had an HC 4 version
of org.apache.hc.core5.http.URIScheme.

Any thoughts on doing so?

Gary