Set default value of annotation.support param to 0 (off). Also,

Set default value of annotation.support param to 0 (off). Also,
wrapped contents of the apply-annotations template in a "if"
statement, so that those contents get evaluated only if
annotation.support is non-zero.

The reason for these changes was a report from Doug du Boulay (on
the docbook-apps list) that processing of the apply-annotations
template was consuming 75% of the total processing time for a
2.5Mb file. Anatoly Techtonik followed with a comment that with
1.69.0, "Compiling took about full working day on 12Mb file while
earlier it was about 2-4 hours".