hg: build-infra/jdk8: * Make "demos" a new top-level make target, and move it out of the jdk target.

[magnus.ihse.bursie at oracle.com]

Changeset: 6ecc779107ac
Author:    ihse
Date:      2012-10-11 15:48 +0200
URL:       http://hg.openjdk.java.net/build-infra/jdk8/rev/6ecc779107ac

* Make "demos" a new top-level make target, and move it out of the jdk target.
* Compile hotspot before corba/jaxp/jaxws for better fail-fast for Hotspot developers.
* Clean up build logic in Main.gmk and BuildJdk.gmk.

! common/makefiles/Main.gmk