Fix: Crashes in certain situations involving receptionists and reception desks.
Fix: Patients being handled at a reception desk even if no receptionist is present.

Fixes issue 743. Fixes issue 1172. Fixes issue 1209.

git-svn-id: http://corsix-th.googlecode.com/svn/trunk@1841 c39591fa-788f-11de-a72b-d90af8dea425