Add a basic java node description

This node installs all current (at time of Vagrant instance spin-up)
OpenJDK versions and then sets the alternatives to use Java7 (aka
OpenJDK 1.7.0). At the time of this definition the following Java devel
systems are available on F20, EL{6,7}:

java-1.6.0-openjdk
java-1.7.0-openjdk
java-1.8.0-openjdk

It is expected that any systems that desire to use either Java6 or Java8
will flip the alternatives themselves on startup.

NOTE: using auto presently still means Java7 as Java8 has a lower
alternatives weight.

Change-Id: I4df978ca5a1a983e4465e6d2695ef2ba4b875adc
Signed-off-by: Andrew Grimberg <agrimberg@linuxfoundation.org>