Add release cadence information to the site

[bstansberry]

Our general practice of releasing a feature release roughly quarterly with one bug fix release per feature release should be written down somewhere on wildfly.org

The 'about' page seems a likely spot. There's no other spot on the top level menu that seems appropriate, and putting this kind of info on some new page not on the top level seems like a way for it to never be noticed.

Perhaps 'about' can have something brief that links to something more verbose.

The key points to cover are things we've stated in various forums over the years:

• WildFly releases frequently, and is aiming to deliver new final versions containing new features in an approximately three month cycle. Typically a release containing new features will have a new major version number. Occasionally the project will release a minor version instead of a major. We also deliver one feature-complete Beta release per major, typically two weeks before the final release, and provide a nightly build for those that wish to be on the bleeding edge. The WildFly Core project, which provides the kernel of WildFly, also produces a major release in a three month cycle that is closely aligned to the WildFly cycle. WildFly Core will typically produce milestone releases every two to three weeks, with WildFly consuming those releases in its master branch very shortly after release.
• The cadence of feature releases is subject to change any time, particularly when critical functionality cannot be delivered in a typical three month release window or be delivered incrementally across several such windows.
• For each major or minor release, WildFly will release a single bug fix micro-version release based on that major or minor. This micro version release will usually be available about a month after the major or minor it is based upon.
• Beyond that single bug fix release, WildFly typically will not release additional bug fix releases based on a particular major or minor. Users are encouraged to move to the next major or minor release in order to consume bug fixes. Occasionally the project may elect to produce more than one bug fix release, but due to the effort involved in doing so this will not be the norm and should never be expected absent an explicit communication from the project lead that such a release is forthcoming.