Add Devise to Gemfile

* Devise is now added to the Gemfile and bundled.

https://github.com/Moneyvate/moneyvate-core/issues/1
Generate Necessary Devise Config Files

* All necessary configuration files have now been generated.
  As a result, Devise models may now be added without issue.

https://github.com/Moneyvate/moneyvate-core/issues/1
Add Note About Production Hostname

* The note is placed to ensure that the production hostname is
  eventually changed to the correct hostname when the app is
  ready to be deployed.

https://github.com/Moneyvate/moneyvate-core/issues/1
Prevent Asset Loading on Precompile

* I'm not sure if it's necessary to disable this option, but
  I'm disabling it just in case it's still required to do so
  for a Rails app on Heroku.

https://github.com/Moneyvate/moneyvate-core/issues/1
Add Home Page

* Added route to home page.
* Added home page with some test copy.
Add Devise User

* User class now added.

https://github.com/Moneyvate/moneyvate-core/issues/1
Add Navigation Bar with Login/Logout Links

* Navigation bar started.
* Added Login/Logout links.

https://github.com/Moneyvate/moneyvate-core/issues/1
Fix Code Formatting

* Corrected hash spacing
* Changed some double quotes to single quotes, since no string
  interpolation was taking place.