Convert incoming messages to utf-8 on ingest

Koha::Edifact used to convert messages to utf8 when processing
Change logic so we convert messages to utf-8 before storing them
in the database. Logic is now in Transport's ingest
Edifact allows ascii or Latin-1 so converting latin1 to utf8
should be a safe option
Make vendor edi accounts editing more user friendly

Add a couple of tool tips and make FTP/SFTP selection a select