fix a bug in izene_read_until.
fix a bug in izene_read_until.

as it calls istream::readsome(), which function stops reading when
the stream buffer is full, even if the End-Of-File has not yet been reached.

so it is revised to call istream::read() instead, which function
continues reading until End-Of-File is reached or n characters are read.

izenecloud/izenelib,pombredanne/izenelib,izenecloud/izenelib,pombredanne/izenelib,pombredanne/izenelib,izenecloud/izenelib,izenecloud/izenelib,pombredanne/izenelib