enabled PDS queries using env flag for use when server is_in_production_mode = 0

spell-check changes: add-new-word function now puts terms in temp file for assessment by admin before importing into site-specific personal dictionary; rebuilt en-medical.rws (extra-dict) from edited contents of old personal dict (.aspell.en.pws) - moved all acronyms/abbreviations into new personal dict (.aspell.leeds.pws); LIMS::_create_user_profile() adds users 'centre' param to session user_profile; adapted spellchecker.pl to work with new dictionary format

disabled C::Ajax::cgiapp_init() due to issues - see inline comments; bugfixes for test suite

enabled en-medical aspell dictionary; temp bugfix in return value from C::Ajax::add_word() until circular ref in local cgiapp_init() is fixed

hilis3 conversion scripts for YHHN