Update rails and sprockets gems

Addresses CVE-2014-7818 and CVE-2014-7819
update gemfile
Statistics for longest running projects now includes completed and hidden projects. fixes #1725
Add a Sidebar class to represent the side bar

Start using it throughout the rest of the app instead of the various
instance variables
Merge pull request #1728 from TracksApp/create-sidebar-container

Add an object to represent the sidebar
Remove support for deprecated password-hashing algorithm

* Remove all methods implementing and checking for the old algorithm
* Document a pre-upgrade step to check for remaining obsolete passwords
* Remove config.salt
Include Travis's default bundler arguments
Upgrade Rails to 4.1.8 to address CVE-2014-7829
Merge pull request #1736 from matjack1/CVE-2014-7829

Upgrade Rails to 4.1.8 to address CVE-2014-7829
Merge pull request #1733 from dnrce/password-hashing

Remove support for deprecated password hashing algorithm