RFR: JDK-8136782: Introduce a build/configure wrapper

[Erik Joelsson]

Hello,

This patch adds support for a new Oracle internal tool that will help us 
manage build configurations. I doubt it could be of any use to outside 
users, except perhaps to give a bit of insight into what versions of 
certain dependencies we use internally, as those will be specified in 
the jab-profiles.js configuration file.

In addition to the JAB configuration files added here, I've also added a 
new configure option --with-default-make-target with which you can 
change the default make target for a configuration. A bug is fixed in 
the configure wrapper script where it's currently not propagating the 
return value of configure. Finally a new make command line variable is 
added, CONF_NAME, which works like CONF, except it only matches exact 
configuration names.

Bug: https://bugs.openjdk.java.net/browse/JDK-8136782
Webrev: http://cr.openjdk.java.net/~erikj/8136782/webrev.top.01/

/Erik