Rename {get|set}FeatureId to {get|set}Id
The production loader has special logic for advanced and raw modes
Merge pull request #1045 from tschaub/advanced

Use "advanced" for the production loader.
Merge pull request #832 from fredj/feature_getset_id

Rename setFeatureId to setId (same for get).
Add styleMap parsing
Fix styleUrl parsing
Add styleMap writer