Adding a virtualenv, readme updates, and an export folder

Hey, this Endomondo parser is great, thanks for creating it!  

I hit a few things while using it, so I made a few updates that I thought you might find helpful too.  If you like it, feel free to merge it, as it might help out others who stumble upon it in the future.  Yours is the only tool I found that actually worked, so it's a great resource to have!

Hope this helps, and totally give me a shout if any of this looks wrong or crazy. =)

Thanks!