Bug 7890: Highlight required field in MARC editor

Bug 7890: Highlight required field in MARC editor

This patch modifies the basic MARC editor so that required fields have
the standard "Required" label on them instead of a small red asterisk.

To test, apply the patch and create a new record in the basic MARC
editor. Tags which are marked mandatory in your selected MARC
bibliographic framework should be labeled "Required."

Signed-off-by: Maryse Simard <maryse.simard@inlibro.com>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>