Bug 21053: Encode URI characters in plugin 008

Bug 21053: Encode URI characters in plugin 008

A # (or &) at any position in 008 field of a bib record causes
all subsequent data in field to be overwritten with default values when
record is saved.

These characters need to be correctly encoded before being passed as
parameters of the url

To reproduce:
1. Find and edit a bib record which has an 008 which differs from the
default values for the MARC framework
2. Choose 008 helper
3. Add # in any position before the end of the field noting the current
values of the data
4. Save record
5. Edit record and select 008 helper
6. Review characters after #

Signed-off-by: Maryse Simard <maryse.simard@inlibro.com>
Followed the test plan and it works.

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>