Allow an 'other' type for hyperlinks. Format change.

Allow an 'other' type for hyperlinks. Format change.

Also, perform the URL fixing magic for DocBook and XHTML.

As it was, it was impossible to enter e.g. "tel:" type links. Now
choosing the "Other" type just outputs the URL as given.

Also, the addition of "http" or "file" was not being done for
DocBook and XHTML. Now it is.