Fixed circle

• Added fixed circle that corrects inconsistent radius size bug.
• Updated all dependencies.

Retina fix

• Changed tile size on retina displays so that entire floorplan fits on iPhone display

Functional tile layer & refactoring

• Added FunctionalTileLayer to support getting tiles from authenticated API
• Removed addTileLayer from Viewer, default options are now in FunctionalTileLayer
• Removed I prefix from interfaces
• Refactoring

Initial version of library

Initial version of the library with support for rendering space vector graphics, showing graphics layers, and selecting and styling spaces and other elements.