Bug 18417: Advanced Editor (Rancor) add shortcuts for copyright symbols (C) (P)

Bug 18417: Advanced Editor (Rancor) add shortcuts for copyright symbols (C) (P)

To test:
1 - Apply patch
2 - Open advanced cataloging editor
3 - Try using Alt+P and Alt+C and note symbols are added
4 - Save record and ensure symbols are saved

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
(cherry picked from commit ff374c3d3e9be828491821356c0b1790fa3d397f)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>