Added capability to merge organisations

- Added an interface for organisation
- Added beforeDelete and beforeMerge callbacks
- Added hard/soft delete to organisations

locale/en_US/messages.php

@@ -27,6 +27,10 @@ return [
         'EDIT'                => 'Edit organistion',
         'UPDATE'              => 'Details updated for organistion <strong>{{name}}</strong>',
 
+        'MERGE'               => 'Merge organisation',
+        'MERGE_INFORM'        => 'Select an organisation from the list below to merge organisation <strong>{{name}}</strong> into. All users of organisation <strong>{{name}}</strong> will be moved into the chosen organisation.',
+        'MERGE_SUCCESSFUL'    => 'Successfully merged organisation <strong>{{source}}</strong> into organisation <strong>{{target}}</strong>.',
+
         'DELETE'              => 'Delete organisation',
         'DELETE_CONFIRM'      => 'Are you sure you want to delete the organisation <strong>{{name}}</strong>?',
         'DELETE_YES'          => 'Yes, delete organisation',
@@ -55,4 +59,12 @@ return [
         1 => 'Administrator',
         2 => 'Administrators',
     ],
+
+    'MERGE'                   => 'Merge',
+    'MERGE_INTO'              => 'Merge into',
+    'MERGE_CANNOT_UNDONE'     => 'This action cannot be undone.',
+
+    'SOURCE_SLUG'     => 'Source Slug',
+    'TARGET_SLUG'     => 'Target Slug',
+    'SLUG_NOT_IN_USE' => 'A <strong>{{slug}}</strong> slug does not exist',
 ];