Add 2.0.12.3 to docs and purge old 2.x versions
Add 2.0.12.3 to docs and purge old 2.x versions

This is mainly to have the latest 2.x in the version dropdown, there
were no doc changes for 2.0.12.3.

mebigfatguy/java-driver,tolbertam/java-driver,mebigfatguy/java-driver,tolbertam/java-driver,mebigfatguy/java-driver,tolbertam/java-driver