added "newer version available" link as per Documentation update process
added canonical link as per documentation update process.
Update wordings of some documenation, and add some more to what's new v2.3
Merge pull request #22 from dpvc/v2.3-latest

Update wordings of some documenation, and add some more to what's new v2.3
merged @dpvc's updates to v2.3-latest into master