Metacat

Use the variable release to replace the hard-coded version.

Use the variable release to replace the hard-coded version. The release variable can be modified on the conf.py file.

Use the |today| which will be auto generated the current date to replace the hard code of the release date.

Change the version and release to 2.8.0.
Add a date format property.

Change the newest version to 2.8.0

Change the version to 2.8.0

Merge changes from the 2.6.0 release.

Remove the servlet part from knb metacat url on the morpho screen.

update documentation to use 2.6.0 release number.

And don't forget the alternate Redhat instructions.

refs https://github.nceas.ucsb.edu/KNB/arctic-data/issues/42