[ixpmanager] IXP Manager documentation now versioned

[Barry O'Donovan (INEX)]

Hi all,

We are working behind the scenes on IXP Manager v7 with a planned 
release in time for the next Euro-IX forum in November.

As each release adds features, we recognise that the documentation can 
become confusing when it is not clear when a feature was introduced.

To resolve this, we have now started versioning the documentation. When 
you browse to https://docs.ixpmanager.org/ you will be redirected to 
https://docs.ixpmanager.org/latest/ by default. 'latest' will always 
reference the last released major.minor version. Currently v6.4.1 is the 
latest release and so https://docs.ixpmanager.org/latest/ will provide 
the 6.4 documentation.

All new documentation will be added to the 'dev' identifier - 
https://docs.ixpmanager.org/dev/ - which currently points to 7.0 in 
preparation for that release.

When 7.0 is released, this will be tagged as latest and 'frozen' with 
new documentation moving to dev/7.1.

Thanks,
  - Barry