Bug 16685 - Use eval instead of do for .perl atomicupdates

Bug 16685 - Use eval instead of do for .perl atomicupdates

If we use eval instead of do for our .perl atomic update files, it will
allow developers to put in the exact code that should go into
updatedatabase.pl. The problem with do is that none of the variables
defined in updatadatabase.pl are available, whereas with eval they are.

Test Plan:
1) Apply this patch
2) Create a .perl file in atomicupdates with the following in it:
say "DBversion: $DBversion";
3) Run updatadatabase.pl
4) Note the output
5) Add a syntax error to your atomic update
6) Run updatedatabase.pl
7) Note the error is displayed

Signed-off-by: Aleisha Amohia <aleishaamohia@hotmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>