Bsdconv

improve alias mechanism
add bsdconv_codec_check()
add bsdconv_codecs_list()
add bsdconv_pack()

improve inter/{zh_decomp,zh_comp}

mac os compatible (thanks to godfat)
improve inter/ZHTW_WORDS
improve inter/ZH_DECOMP and inter/ZH_COMP

improve cross-codecs communication
inter/WHITESPACE-DERAIL
inter/WHITESPACE-RERAIL

reduce memory usage in bsdconv_mktable
inter/WIDTH
to/NULL

table format change
inter/SCORE
inter/SCORE_TRAIN
refactor bsdconv_create()
add bsdconv_insert_phase()
add bsdconv_insert_codec()
add bsdconv_replace_phase()
add bsdconv_replace_codec()
add bsdconv_get_phase_index()
add bsdconv_get_codec_index()
add bsdconv_duplicate()
add bsdconv_ctl() and cbctl() in callback mechanism