* Automatic dark/light colorschemes
A new `colorscheme` option is added with the capability to be always dark,
always light, or automatic based on the user's browser setting. This
makes the `inverted` option superfluous, and therefore deprecated.
Nomenclature of files, variables, etc are changed from `inverted` to
`dark` to reflect this change.
Closes#226.
* Remove inverted option completely
The `inverted` option is now not just deprecated, but removed
completely.
John Schroeder