Provide dates, versions numbers, list of changes in Code Manager

[#1]

In the Code Manager, there's currently no way to tell if there are new versions of libraries short of downloading the same library again and doing a binary compare.  You could make this easier for us in several ways, but at the very minimum providing the date of the most recent update of each library would be a huge help.  Beyond that:

-- Associate version numbers with libraries

-- List the changes implemented with each version

-- Allow us to sign up for notifications when a library is updated