Used to perform a pre-load of pages, at startup time. This helps ensure that the first actual
request is processed promptly.
The configuration is simply the logical names of pages to load initially.
Pages are loaded in the default locale (the first locale listed in
SymbolConstants.SUPPORTED_LOCALES). This ensures that the majority
of class loading and transformation, template parsing, and so forth occurs immediately (loading
an existing page in a different locale is a relatively inexpensive operation compared to the
first load of the page).