Prefixes on index page are not up-to-date

[Steven Maude]

Manually edited, rather than pulled from the prefix dictionary that's used.

[ian_hopkinson]

The prefixes used in queries, the prefixes shown as help on the index page and the prefixes used in shortening are all entered independently.

[ian_hopkinson]

Fixed by 6914040 in pull request #102.

PREFIX shortening in the HTML output not addressed.