espeak/en: additional mapping rules based on output from 'The Raven'
espeak/en: support en-sc transcriptions
ipa: support FIR and FUR vowels (pre FERN-FIR-FUR merger)
x-sampa: support START, FORCE, NORTH, FIR and FUR vowels
cxs: support START, FORCE, NORTH, FIR and FUR vowels
espeak/en: support en-uk-north transcriptions
espeak/en: support en-uk-rp transcriptions
espeak/en: support en-uk-wmids transcriptions
espeak/en: support en-us transcriptions
espeak/en: support en-wi transcriptions