bulkmarcimport: enable MARC-8 to UTF-8 conversion

bulkmarcimport: enable MARC-8 to UTF-8 conversion

Enabled automatic conversion of MARC-8 records to
UTF-8.  Record is converted if its Leader/09 contains
a blank and the -s (skip) option hasn't been supplied
on the command-line.  Any record that cannot be converted
to UTF-8 is skipped.

Also now use Unicode Normalization Form C (NFC) for
records converted from MARC-8.

Signed-off-by: Chris Cormack <crc@liblime.com>
Signed-off-by: Joshua Ferraro <jmf@liblime.com>