Celtic suggestions

Hi Superpat, 

Here are some small suggestions to improve the Celtic mechanics. 
I've tested all, except the reincarnation: event doesn't trigger from console, not sure why...
I can adapt and/or drop some of the changes based on your review.

1- Druidic temple holders also get the druid trait on nomination: seems more logical as they are called Druids after all ^^
2- Court druid has to be courtier (not a vassal):  it's consequence of 1, otherwise it would be too easy with all the druid religious vassal.
3- Reminder for no court druid with auto-suggest: enable the yearly reminder of no court druid, with an auto-suggest in case of a suitable candidate is present in court.
4- Wicked druid trait: opposite to druid trait, similar to SoA bad priest traits.
5- Sympathy traits: restoring the old Celtic rites gives trait sympathy for pagans, and converting gives sympathy for christians. Makes the restoration/conversion process more smooth as vassals may switch at different pace, and a bit less pressure on 1st converted ruler.
6- Reincarnation events: based on RoI event chain.