header files of libiconv-hook

 This code is iconv compatible interface routine for mod_encoding.
 Taisuke Yamada writes sample code for hooking iconv() for mod_encoding.
 .
 In mod_encoding configuration directive,
 supports following encoding names additionally:
 .
  MSSJIS
  - This is almost same as SJIS, but is a Microsoft variant of it.
 .
  JA-AUTO-SJIS-MS
  - This is a special converter which does autodetection between
    UTF-8/JIS/MSSJIS/SJIS/EUC-JP. This itself does not do conversion.