This is just a simple wrapper around the API from BioMart, but I found existing packages were not quite sufficent for what I was wanting to do.
Here you can simply get the list of all genes and perform other biomart functions such as mapping between human and mouse.
It is available under the GNU General Public License (Version 3).
Please post questions and issues related to sci-loc2gene on the Issues section of the GitHub repository.
Make a pull request on github.