Added virtualenv and Heroku Procfile
Moved venv in gitignore
Added requirements.txt file
Refactored code to support multiple database engines

Application can now support multiple database engines.
Added config file for dev/prod mode

Added a configuration file to easily distinguish between development
and production modes.
Added PostgreSQL database wrapper (#9)

Added a Database class that wraps around PostgreSQL basic functionality.
Updated schema (#9)

Updated database schema to adapt to PostgreSQL.
Removed support for multiple database engines (#9)

Removed support for multiple database engines as abstraction became
difficult to implement.
Changes in queries to reflect new schema (#9)

Changed how parameters are passed to queries (using %s) and how times
are saved.
Added psycopg2 module to requirements.txt (#9)
Updated .gitignore

Removed .DS_Store files from repository.
Housekeeping

Changed environment to production and removed the host from app.run().
Merge pull request #10 from linkyndy/postgresql-integration

Postgresql integration
Resolved merging conflicts
Added pyechonest to libs
Changed requirements.txt