When opening a file for a stream, check for UTF-8 BOM. When we find a BOM, we skip it, and we mark the stream as being UTF-8.  Then we can (and do) skip conversion with iconv, so that on (e.g.) Windows you can run mclient with some encoding set, but still read UTF-8 encoded files, as long as they start with the BOM. This fixes bug 3436.
When opening a file for a stream, check for UTF-8 BOM.
When we find a BOM, we skip it, and we mark the stream as being
UTF-8.  Then we can (and do) skip conversion with iconv, so that on
(e.g.) Windows you can run mclient with some encoding set, but still
read UTF-8 encoded files, as long as they start with the BOM.
This fixes bug 3436.

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb