The use of Locale.LanguageRange for the Accept-Language header makes
sense as it gives the most flexibility for a client to set a weighted
list and for a server to do filtering via Locale#filter.
This commit adds an additional convenience method that turns
the LangugeRange list to a list of Locale's also filtering out a
wildcard (i.e. "*"). A List<Locale> is the most basic way to access
prefered languages and needed when filtering is not required.
Issue: SPR-15024