Allows for smaller SOLR index when using locales that share a language.    Before, if an installation had locales for "en", "en_US", and "en_UK" all translatable fields would be indexed for all three of these locales.    The `Locale.getUseCountryInSearchIndex()` can be set to true if this behavior is still desired.   Otherwise, all three of these Locales will be indexed as "en".   Addresses enhancement #62.