More housekeeping

* Template directory names can now be specified as a build parameter.
* DEBUG_NAMEs can now be specified as a build parameter, for naming builds arbitrarily.
* MESS perf indicator functions are now permanently exposed.
* `pre.js` and `post.js` are now part of the templates.
* Version and build information are now stuffed into a JSMESS variable.
* Perf indicator JS functions are now stuffed into a JSMESS variable.