Bug 10256: Remove some unused subs from Overdues module

Bug 10256: Remove some unused subs from Overdues module

Removes the following exported but unused subs from Overdues.pm:
CreateItemAccountLine
UpdateAccountLines
CheckAccountLineLevelInfo
CheckAccountLineItemInfo
CheckExistantNotifyid
GetNextIdNotify
GetNotifyId
ReplacementCost
ReplacementCost2
GetOverdueDelays
GetOverduerules

Test plan:
It is hard to test the removal of something that was not used :) Try this:
Do a recursive grep on these routine names in the Koha codebase.
Compile some scripts that use the Overdues module.
And just to be sure we do not break something:
Go to Circulation: Do a checkout, checkin, place and confirm a hold.
Go to Patrons: Goto Check out. Goto Fines.
Run the command line scripts: fines.pl and overdue_notices.pl.
Go to opac-user.pl.

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>