Bug 29121: Catch errors in ->install and ->upgrade calls on plugins

Bug 29121: Catch errors in ->install and ->upgrade calls on plugins

This patch adds a try/catch block when instantiating plugins. Calling
->new on a plugin eventually triggers a call to ->install (this has
always been like this since bug 7804). If the ->install method is
somehow borked, then the process dies. We need to prevent that, and
report back some error took place. That's what this patch does.

The same happens to the ->upgrade.

To test:
1. Install any plugin you like
2. Restart plack (just in case)
=> SUCCESS: All good
3. Manually change its install method to:

sub install {
    die "plugin, die!";
}

4. Run:
   $ koha-mysql kohadev
   > DELETE FROM plugin_data;
(to make sure there's no __INSTALLED__ entry, do on a safe to delete DB).
5. Point your browser to the plugins-home.pl page
=> FAIL: Boom
6. Apply up to the regression tests
7. Run:
   $ kshell
  k$ prove t/db_dependent/Koha/Plugins/Plugins.t \
           t/Koha/Exceptions.t
=> FAIL: Tests fail!
8. Apply this patch
9. Repeat 2
=> SUCCESS: Tests pass!
10. Run:
    $ restart_all
11. Repeat 5
=> SUCCESS: The page is not broken
12. Sign off :-D

Note: I used
    $ kshell
   k$ perl misc/devel/install_plugins.pl
to test as well.

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>