[Tilesathome] Promoting/demoting items

[David Earl]

I'd like to suggest the following changes in the osmarender zoom levels 
for T at H. I'm happy to implement them if there aren't major objections.

(1) Churches are currently rendered only at zoom 17. I think these are 
substantially more prominent landmarks than many other features already 
rendered at lower zoom levels. Therefore I propose:
   - place_of_worship rendered as the usual symbol, possibly a little 
smaller, at zoom 15
   - additionally with its name and larger icon in 16 and 17

(also, the church symbol has got squished since the triangle symbol was 
introduced for religion-less places of worship, so fix that)

(2) Render mini_roundabout and traffic_signals consistently. Currently 
mini_roundabouts appear at 15 and traffic_signals at 17. I propose both 
appear at 16.

(3) Render names of restaurants at zoom 17 (icon is already present).

(4) place=village currently appears at zoom 13. I'd like to move this up 
to zoom 12 - having now done many villages around Cambridge the zoom 12 
map looks very bald.

(5) highway=tertiary currently appears in zoom 12. I'd like to promote 
this to zoom 11. (BTW, I think the recent changes to lower zooms is a 
bug improvement - much clearer rendering of place names).

(6) Render shop=<anything> with same icon as supermarket and name at zoom 17

David