NewFeatures: Chronological entries

New: #pragma search ...

I got tired of the relative links in my blog drafts (written in an entirely different directory than their eventual home) not working. So, introducing #pragma search; this adds additional directories to search for pages when resolving relative links, both WikiWords and explicit [[...]] links. The directories listed in a search pragma must be absolute path names, and are searched only after the hard-coded possibilities have been exhausted (including the alias directory for WikiWords).

You can't have both a #pragma search ... and a #pragma pre in the same page, partly because it doesn't make any sense. (This is the simple way of getting out of handling multiple #pragma directives.)