Add Jasmine tests for Grunt 4.0.X w/ coverage

Builds on https://github.com/Esri/Terraformer/pull/95 adding Jasmine tests and code coverage.

Other key things...
* coverage, complexity and grunt temp files are ignored from build
* jasmine files have been removed
* minified files now have their own directory in "dist"
* structure of the "spec" folder has been simplified.