resolve #142 - modernise examples and perldoc

various commits related to this (all related to #142). namely:

 * use strict
 * use warnings
 * replace any use of HTML generating functions with Template::Toolkit
 * add tests
 * anything else that makes sense

most notably all *documentation* for HTML functionality in CGI has
been moved into its own namespace: CGI::HTML::Functions - although
the functionality continues to exist within CGI.pm so there are no
code changes required. this is done to strongly discourage the use
of the HTML functions within any code that uses CGI.pm

Changes

@@ -9,6 +9,9 @@
 
     [ DOCUMENTATION ]
     - Fix some typos (GH #173, GH #174)
+    - All *documentation* for HTML functionality in CGI has been moved into
+      its own namespace: CGI::HTML::Functions - although the functionality
+      continues to exist within CGI.pm so there are no code changes required
 
     [ INTERNALS ]
     - Cwd made a TEST_REQUIRES rather than a BUILD_REQUIRES in Makefile.PL