Version 0.18.0

Moving to ES6.

The api should remain mostly the same. The only major difference is that java-deserializer, libtga, and gl-matrix are compiled in, and don't need to be included on the page anymore. gl-matrix might still be worth including, however, and can now be found in node_modules, rather than bower_components.

In fact, all three are now npm dependencies, rather than bower dependencies.