Add essential installation information into selected files

This update contains documentation updates only, no code changes. The readme.txt, ipaddr-to-arin-cidr.php, and index.php files now include essential installation configuration notes which were omitted in the previous release.

Simplify integration/deployment to web site

Previous versions were very difficult to integrate into WordPress web sites, and equally tricky to maintain. This version simplifies integration of the project into WordPress and other web sites, by allowing the definition of working directories.

Code cleanup, no functional changes

Removed dead code related to IPaddressValidator class.

Revised author email address

It still works for me...

Improved documentation in headers, reformatted code for readability

v1.0.1

Improved documentation, reformatted code for readability

Initial release

Works for me