Bug 6869 Batch item modification fails whit accented characters

Bug 6869 Batch item modification fails whit accented characters

Corrects a problem in batchMod.pl when accented characters are used.

When modifying multiple items in batchMod.pl, the batch modification
fails if accented characters are used in any of the fields of the
modification form.

This is a port of Frédérick Capovilla patch from 3.2 to 3.4 version

Signed-off-by: Ian Walls <ian.walls@bywatersolutions.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>