Add MongoDB ActiveRecord library for CodeIgniter

Source: https://github.com/alexbilbie/codeigniter-mongodb-library/tree/v2
License: MIT License

Config file currently set up to connect to MongoDB database with no password. Once live server is set up, config file will (obviously) need to be edited to match the password of the MongoDB installation there.
Add MongoDB session library for CodeIgniter

Source: https://github.com/sepehr/ci-mongodb-session
License: CodeIgniter License Agreement
Improve session cookies

Based on the advice at http://christopherickes.com/web-app-development/3-codeigniter-sessions-best-practices/, I've turned on encrypted session cookies, and removed the underscore from the session cookie name (which allegedly causes problems in IE -- the only facts I could find to back up that claim had to do with underscores in domain names, not in cookie names, but in this case it won't hurt to be extra cautious.)
Add Ion Auth 2

Note: After pulling this commit, you need to go to the src/ directory and run "mongorestore sql/mongo". The sql/ directory can then be deleted, as this is a one-time setup to load Ion Auth's user & group collections into MongoDB.

Source: https://github.com/benedmunds/CodeIgniter-Ion-Auth (branch 2)
License: Apache License v2.0
added placeholder templates for front page links
got ride of base_page and created nested view templates
created js/lib folder and moved resources into that folder
shorten the slides/promotion area by 100px
added 4 frontpage images
added js/lib path to scripts template
break out slideshow and 3column display into separate templates
adjusted slideshow height again
added marketing fluff
wip: design docs
wip: design
wip: design added My Projects
Config changes to enable MongoDB with Ion Auth

Default Mongo database name is "mongo" for now, but we
could easily change that to whatever we want: sfweb, maybe.
Autoload the Ion Auth library
Use a (randomly-generated) session encryption key
wip: design added Activity