Add _exit(...) function to pointFeature

Need to remove actor from render context.
Add clear(...) method to featureLayer

Method to remove all featured associated with the layer.
Add animation events
Add animation support to map

Add support for animating layer over a global time range.
Remove trailing whitespace
Add test for animation support
Add support to share a single GL context between layers

Share a single viewer between all vglRenderer instances so they
can share the same GL canvas.
Move VGL submodule forward
Allow OSM base URL to be configured

Allow the base URL to be past to the constructor.
refactoring phantomjs unit tests
Only register events for base layer
support python 3 for test runner
Fix style issues
Adding cmake variables for testing config
adding phantomjs cmake plugin
adding initial js coverage reporting
adding jquery to unit tests
removing outdated package.json
adding travis config
reducing cmake requirement to 2.8 for building on travis