Optionally set a separate Javascript server and path

Optionally set a separate Javascript server and path

We have about 10-12 JavaScript pages per Web page. They usually
are based on the same server as the Web pages, but since they're
static files, it makes sense to offload them to a lite server that
handles static files well.

This commit lets you set a separate Javascript server and path for the
default Javascript code in StatusNet.

Squashed commit of the following:

commit 139d1622fdafe5ad00c820224416d9021efc3234
Author: Evan Prodromou <evan@status.net>
Date:   Wed Jan 27 11:30:24 2010 -0500

    modules that call htmloutputter::script() don't prescribe js/ path

commit c6ca3174af73efed55eaed5ff1e2a3bdc77d2d87
Author: Evan Prodromou <evan@status.net>
Date:   Wed Jan 27 11:28:07 2010 -0500

    configurable server and path for javascript files