fixed versioning for the packaging system.
Added capability to search for packages.
Refactored the package versioning and exposed a version API.

We now have an API that lists known versions for packages that use the
gophe.rs packaging system.

There is now an interface for external sources that allows for other
public repos to be used. Git is currently implemented for github and
bitbucket.
Various changes. Sorry for the lack of multiple commits, still in the
early stages.

* We now use the g.gophe.rs/v2/icub3d/semver package for versioning.

* There are now some Cache DatastoreFuncs that are used, particularly
  in the larn section.

* Added a fetch.go file. It contains a wrapper around
  appengine/urlfetch that tries memcache first. Most of the urlfetch
  pages now use that (twitter being the exception).

* Added the packaging functionality for multiple versions.
removed todo list, use github issues.
Added about modal.
#4 - Added help message.
Fixed issues #1 and #3 and renamed learn section to articles.

* We now have a history that is maintained. There is currently no
  interface, but that could be added later.

* The history keeps all the additional files as well.

* We now refer to the learn section as the article section.