Add unit tests for Inflector functions.
Add UTF8::clean() call to Encoding::convert_to_utf8(), remove from Exif::extract()
- no net effect for Exif::extract().
- effectively adds UTF8::clean() call to Hook_TagEvent::item_created().
- also, clarify EXIF comment while we're here.
Fix HTTP_ACCEPT_LANGUAGE use in Locales::locale_from_http_request().
Add purifier module to packager and install.sql.
Merge pull request #278 from shadlaws/misc_fixes_20130409

Misc fixes 20130409