Contains postlexical rules to solve problems concerning the lexicon:
1. transforms some ich to ach-sounds (for Celex dict. only)
2. joins affricates
3. prevents some unknown diphones (for Celex dict. only,
should not be here but in diphone module)
4. give syllables names (transcription of phones in syllables)
5. inserts glottal stops of length glottal_stop_len
(for Celex dict. only, default:0.001s)
6. maps R to aschwa at the end of syllables