This version focuses on fixing bugs and WebGL examples implement, and this should be the last version which still supports deck.gl @v6.4.x (since deck.gl has updated to v7.3.x).

Major modifications includes:

1. WebGL example codes (within WEBGL_EXAMPLES folder);
2. IconLayer demo with different data loading approach (CSV with d3 module);
3. Bugfixes and deps update;