Added support to feature layer to the map
Updated renderer class to current syntax and style
Fixing some more style
Various fixes to the get the layer api working
Adding blend attribute
Improving vgl code
Some more improvements
Consistent code style
Some more fixes
Improving test interface
Added slider to control opacity
Implementing the layer opacity function
Removed hard-coded width and height
Removed debug messages
Fixed code style
Removed last bits of debug message
Added missing files
Merge remote-tracking branch 'origin/enhance_map_api'

* origin/enhance_map_api:
  Added missing files
  Removed last bits of debug message
  Fixed code style
  Removed debug messages
  Removed hard-coded width and height
  Implementing the layer opacity function
  Added slider to control opacity
  Improving test interface
  Some more fixes
  Consistent code style
  Some more improvements
  Improving vgl code
  Adding blend attribute
  Various fixes to the get the layer api working
  Fixing some more style
  Updated renderer class to current syntax and style
  Added support to feature layer to the map