Remove extra information from README now that it is present on the wiki.

 - Change test results to list those from TravisCI instead of @MiguelCastillo's computer.
 - Update download link version.

I have not moved the download, build, and install information as I consider that to be fine (and better) in the README than on the wiki, because the README is used by `npmjs.com` (for example) to provide information about the package. I've also updated the Table of contents to match the new contents.

The API documentation has been moved, see it [here](https://github.com/MiguelCastillo/spromise/wiki/API)