Merge pull request #1 from edsalisb/master

Made an investment model and controller, and the new investment view usi...
installed devise gem
Merge pull request #2 from edsalisb/master

Commit 2 by Ethan: made the model methods
Merge pull request #3 from edsalisb/master

Ethan's commit #3: Fixed the model for investments.rb
updated views
Merge branch 'master' of https://github.com/maribelb/buynot
Merge pull request #4 from edsalisb/master

Ethan's Commit #4: Fixed the Investments controller... I think
edited views
updated views and style sheets