site/canon/search/index.cgi: Comment cleanup.

+ Some very minor refactoring.
site/canon/search/index.cgi: Refactoring.

* Rewrote old_form() to be a bit smarter about its arguments, thereby
  replacing xx() and empty_form() functions.
site/canon/search/index.cgi: More refactoring.

old_form() now uses named arguments.
site/canon/search/index.cgi: Even more refactoring.

* Renamed display_file() -> file_page().

* Rewrote file_page() to return() result instead of printing.

* Some other reformatting / commenting.

* Removed a bunch of functions that are no longer in use.
Added package for page header & footer in CGI.

* Added to `/canon/show.cgi` and `/canon/search/index.cgi`.

* The package called 'Local::Page' and is included inline in both these
  script, so far. It should be separated in to its own file and
  'use':ed, in the end.
Search now always uses 'q' instead of 'query'.

* The `site/canon/search/index.cgi` CGI script now always uses 'q' as
  the GET form field name, instead of 'query' ('query' is still
  supported, however, so that any old bookmarks will continue to work).
  This means that all links displayed on result pages etc, refer to the
  new 'q' field.
Fixed broken "transcript" link in Canon Search.

The search result page of the "Archive of Okrandian" had non-functioning
"Transcript" links for each search result. Fixed that.