Photoes; no sending credentials via network; offline mode

Hi!

I added some changes:

- winner photoes (using meetup users pictures, no resizing, using as it is);

- no email passwords (this change means that there is a special email user for a role of sender; there will be no need in exposing your own email account password to the application; credentials of this test-user are put into external local file /etc/meetup.conf; to use this file it's necessary to always run the application via ./sbt and not as just sbt (/usr/bin/sbt). You won't loose this info in the future - I put all the instructions to README file; I also sent you content for /etc/meetup.conf via email to remain hidden from the internet, don't forget to put it to the right location and edit properly);

- offline mode (for developing purposes I added a mode working with no internet access; to activate this mode comment the line at Boot.scala).