Fixing app.yaml plus cosmetic things

Fixing app.yaml as it was previously broken on my local installation,
conf borrowed from SO:

- http://stackoverflow.com/questions/21581182/google-app-engine-wordpress-update-failure

Cosmetic things:
- tabs to spaces
- YOUR_PROJECT_ID more consistent now
addressing further points by johndylan@
Merge pull request #16 from palladius/master

Fixing app.yaml plus cosmetic things