Cemeteries and Headstones: WNY, New Brunswick and Minnesota Roots

In the list of cemeteries within the selected location,
1. Adds a heading that shows the selected location.
2. Adds a button that can cause the page to display all cemeteries within the location.
3. Shows the number of burials in each cemetery in the cemeteries list.
4. The selected location is always a common suffix in all cemeteries, and is removed for display. For instance, in a list of Cemeteries in "Erie County, Ohio, USA":
  - "Hope Cemetery, Erie County, Ohio, USA" => "Hope Cemetery" and
  - "Old Harbor Burial Ground, Clinton, Erie County, Ohio, USA" => "Old Harbor Burial Ground, Clinton"
5. A mod option controls the visibility of each cemetery's Headstones table and of a "Show Headstones" or "Hide Headstones" button.
6. Another mod option controls how many cemeteries will normally be listed on a page before the list breaks to another pagefull.
7. More subtly, "Headstones" are now defined the same way they are in showmap.php. (See the Wiki article for details.)
A "Select Another Location" button that links back to cemeteries.php has been added at the bottom of the page.