Basic implementation for Travis CI

Created by: Ede123

Here's a very basic implementation to use Travis CI, since it is time to tackle #31 (closed) to prevent glitches like #51 in future.

In principle it already works as tested in my fork. So far it installs Scour, checks the installation by calling scour --version and runs testscour.py. For example the initial build of master failed, but my dummy pull request made it pass.

This is not (yet) meant to be a final PR, but to start discussion on what should be implemented (I'm just getting started with CI myself and am learning as I go), so let me know what you think. On the other hand it seems to me even this basic functionality is already a big help and we probably don't even need much more...