Rewrite respond-to to use maps
Renamed properties to the values they're querying

Current context function is space separated list, not comma separated list
Rewrote Context to use Maps instead of cra cra lists
Renamed context-placeholder query-count. Moved append loop to end of parser

By moving the `false` append loop to the end of parser, we remove and ambiguity with where isn't being called.
Merge branch '2.x.x-sass-3.3.0' of github.com:Team-Sass/breakpoint into 2.x.x-sass-3.3.0

* '2.x.x-sass-3.3.0' of github.com:Team-Sass/breakpoint:
  Rewrite respond-to to use maps

Conflicts:
	stylesheets/breakpoint/_respond-to.scss