add Dice example
adds week4 directory and placeholder schedule
updated weekly schedule
exercises
updates minitest to rspec
add db example stuff
add warm up image
update weekly overview
update weekly overview
updates tuesday's schedule to include field trip to big data conference
Merge pull request #33 from Ada-Developers-Academy/week4

Week4
Merge branch 'master' of https://github.com/Ada-Developers-Academy/daily-curriculum